1
|
Martínez JA, Langguth IC, Olivenza-León D, Morgenstern K. The structure-giving role of Rb + ions for water-ice nanoislands supported on Cu(111). Phys Chem Chem Phys 2024; 26:13667-13674. [PMID: 38563329 DOI: 10.1039/d3cp05968e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/04/2024]
Abstract
We characterize the effect of rubidium ions on water-ice nanoislands in terms of area, fractal dimension, and apparent height by low-temperature scanning tunneling microscopy. Water nanoislands on the pristine Cu(111) surface are compared to those at similar coverage on a Rb+ pre-covered Cu(111) surface to reveal the structure-giving effect of Rb+. The presence of Rb+ induces changes in the island shape, and hence, the water network, without affecting the nanoisland volume. The broad area distribution shifts to larger values while the height decreases from three bilayers to one or two bilayers. The nanoislands on the Rb+ pre-covered surface are also more compact, reflected in a shift in the fractal dimension distribution. We relate the changes to a weakening of the hydrogen-bond network by Rb+.
Collapse
Affiliation(s)
- Javier A Martínez
- Instituto de Ciencia y Tecnología de Materiales (IMRE), Universidad de La Habana, Zapata y G, Havana 10400, Cuba.
- Lehrstuhl für Physikalische Chemie I, Ruhr-Universität Bochum, Universitätsstraße 150, D-44801 Bochum, Germany
| | - Inga C Langguth
- Lehrstuhl für Physikalische Chemie I, Ruhr-Universität Bochum, Universitätsstraße 150, D-44801 Bochum, Germany
| | - David Olivenza-León
- Lehrstuhl für Physikalische Chemie I, Ruhr-Universität Bochum, Universitätsstraße 150, D-44801 Bochum, Germany
| | - Karina Morgenstern
- Lehrstuhl für Physikalische Chemie I, Ruhr-Universität Bochum, Universitätsstraße 150, D-44801 Bochum, Germany
| |
Collapse
|
2
|
Qiu X, Chen M, Wu P, Li Y, Sun L, Shang Z, Wang T, Dang Z, Zhu N. Influence of dissolved organic matter with different molecular weight from chicken manure on ferrihydrite adsorption and re-release of antimony(V). JOURNAL OF ENVIRONMENTAL MANAGEMENT 2024; 358:120883. [PMID: 38631167 DOI: 10.1016/j.jenvman.2024.120883] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/26/2024] [Revised: 03/26/2024] [Accepted: 04/10/2024] [Indexed: 04/19/2024]
Abstract
Applying organic fertilizer is the main way to enhance soil fertility through the interfacial reaction between mineral and dissolved organic matter (DOM). However, the interfacial reaction between minerals and DOM may influence antimony(V) (Sb(V)) mobility in agricultural soils around antimony mines. In our study the ferrihydrite (Fh) was chosen as a representative mineral, to reveal the effect of its interaction with chicken manure organic fertilizer (CM-DOM) with Fh on Sb(V) migration. In this study, we investigated different organic matter molecular weights and C/Fe molar ratios. Our findings indicated that the addition of CM-DOM decreased the adsorption of Sb(V) by Fh and promoted the re-release of Sb(V) adsorbed on Fh. This effect was enhanced by increasing the C/Fe molar ratio. Fh mainly affects its interaction with Sb(V) through electrostatic gravitational interaction and ligand exchange, but the presence of CM-DOM weakens the electrostatic interaction between Fh and Sb(V) as well as competes with Sb(V) for the hydroxyl reactive site on Fh surface. In addition, the smaller molecular weight fraction (<10 kDa) of CM-DOM has higher aromaticity and hydrophobicity, which potentially leads to more intense competition with Sb(V) for the reaction sites on Fh. Therefore, the application of organic fertilizer may promote Sb(V) migration, posing significant risks to soil ecosystems and human health, which should be a concern in field soil cultivation.
Collapse
Affiliation(s)
- Xiaoshan Qiu
- School of Environment and Energy, South China University of Technology, Guangzhou Higher Education Mega Centre, Guangzhou, 510006, PR China
| | - Meiqing Chen
- School of Environment and Energy, South China University of Technology, Guangzhou Higher Education Mega Centre, Guangzhou, 510006, PR China; School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou 510006, PR China.
| | - Pingxiao Wu
- School of Environment and Energy, South China University of Technology, Guangzhou Higher Education Mega Centre, Guangzhou, 510006, PR China; The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters, Ministry of Education, Guangzhou, 510006, PR China; Guangdong Provincial Key Laboratory of Solid Wastes Pollution Control and Recycling, Guangzhou, 510006, PR China; Guangdong Engineering and Technology Research Center for Environmental Nanomaterials, Guangzhou, 510006, PR China.
| | - Yihao Li
- South China Institute of Environmental Science, Ministry of Ecological Environment, Guangzhou, 510655, PR China
| | - Leiye Sun
- School of Environment and Energy, South China University of Technology, Guangzhou Higher Education Mega Centre, Guangzhou, 510006, PR China
| | - Zhongbo Shang
- School of Environment and Energy, South China University of Technology, Guangzhou Higher Education Mega Centre, Guangzhou, 510006, PR China
| | - Tianming Wang
- School of Environment and Energy, South China University of Technology, Guangzhou Higher Education Mega Centre, Guangzhou, 510006, PR China
| | - Zhi Dang
- School of Environment and Energy, South China University of Technology, Guangzhou Higher Education Mega Centre, Guangzhou, 510006, PR China; The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters, Ministry of Education, Guangzhou, 510006, PR China; Guangdong Provincial Key Laboratory of Solid Wastes Pollution Control and Recycling, Guangzhou, 510006, PR China
| | - Nengwu Zhu
- School of Environment and Energy, South China University of Technology, Guangzhou Higher Education Mega Centre, Guangzhou, 510006, PR China; The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters, Ministry of Education, Guangzhou, 510006, PR China
| |
Collapse
|
3
|
Yin H, Yan YW, Fang W, Brune H. Probing Catalytic Sites and Adsorbate Spillover on Ultrathin FeO 2-x Film on Ir(111) during CO Oxidation. ACS NANO 2024; 18:7114-7122. [PMID: 38377596 PMCID: PMC10919091 DOI: 10.1021/acsnano.3c11400] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/16/2023] [Revised: 02/06/2024] [Accepted: 02/08/2024] [Indexed: 02/22/2024]
Abstract
The spatially resolved identification of active sites on the heterogeneous catalyst surface is an essential step toward directly visualizing a catalytic reaction with atomic scale. To date, ferrous centers on platinum group metals have shown promising potential for low-temperature CO catalytic oxidation, but the temporal and spatial distribution of active sites during the reaction and how molecular-scale structures develop at the interface are not fully understood. Here, we studied the catalytic CO oxidation and the effect of co-adsorbed hydrogen on the FeO2-x/Ir(111) surface. Combining scanning tunneling microscopy (STM), isotope-labeled pulse reaction measurements, and DFT calculations, we identified both FeO2/Ir and FeO2/FeO sites as active sites with different reactivity. The trilayer O-Fe-O structure with its Moiré pattern can be fully recovered after O2 exposure, where molecular O2 dissociates at the FeO/Ir interface. Additionally, as a competitor, dissociated hydrogen migrates onto the oxide film with the formation of surface hydroxyl and water clusters down to 150 K.
Collapse
Affiliation(s)
- Hao Yin
- Institute
of Physics, École Polytechnique Fédérale
de Lausanne (EPFL), 1015 Lausanne, Switzerland
| | - Yu-Wei Yan
- Department
of Chemistry, Collaborative Innovation Center of Chemistry for Energy
Materials, Shanghai Key Laboratory of Molecular Catalysis and Innovative
Materials, Fudan University, Shanghai 200438, China
| | - Wei Fang
- Department
of Chemistry, Collaborative Innovation Center of Chemistry for Energy
Materials, Shanghai Key Laboratory of Molecular Catalysis and Innovative
Materials, Fudan University, Shanghai 200438, China
| | - Harald Brune
- Institute
of Physics, École Polytechnique Fédérale
de Lausanne (EPFL), 1015 Lausanne, Switzerland
| |
Collapse
|
4
|
Alimohammadian M, Azizian S, Sohrabi B. Preparation of the graphene-based smart hydrophobic nanocomposite and its application in oil/water separation. Sci Rep 2023; 13:19816. [PMID: 37957214 PMCID: PMC10643443 DOI: 10.1038/s41598-023-46520-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2023] [Accepted: 11/02/2023] [Indexed: 11/15/2023] Open
Abstract
Designing and synthesizing materials with smart hydrophobicity against an external magnetic field for efficient oil/water separation is of great importance due to the increasing problems caused by oil pollution. Here, the nanocomposites were fabricated based on graphene and different iron oxides exhibit smart hydrophobicity against an external magnetic field and they are in powder form eliminating the requirement for a substrate employing a facile and echo friendly method. The results prove that autoclaving of graphene leads to its ferromagnetic property; then it is attached to iron oxides by magnetic attraction and a nanocomposite is produced. The magnetic property of the resulting nanocomposite is higher than the magnetic property of its individual components. In addition, following nanocomposite formation, its hydrophobicity and surface area also change. FESEM images were taken from the nanocomposites to study their surface morphology, and EDS-MAP analysis to observe the elemental distribution uniformity of the nanocomposites. Also, to measure the surface area and pore size, BET analysis has been performed on pure materials and graphene-black iron oxide nanocomposite (graphene@black iron oxide). The results show that the specific surface area of black iron oxide increases after being composited with graphene dispersed at 5000 rpm. Indeed, graphene forms a composite by binding to iron oxide, and therefore, its specific surface area increases compared to iron oxide and graphene alone. These results show an increase in oil sorption and better separation of oil from water by the prepared nanocomposite. Also, to measure the magnetic properties of pure materials, graphene@black iron oxide, and ferromagnetic graphene at 3000 and 5000 rpm, the Vibrating Sample Magnetometer analysis has been performed. The results have proven that the nanocomposite powder prepared by a simple method obtained from cost-effective and available materials is hydrophobic and becomes more hydrophobic by applying an external magnetic field. Due to the ease with which oil can be readily removed from the nanocomposite by eliminating the external magnetic field, this nanocomposite is an excellent choice for the separation of oil from water.
Collapse
Affiliation(s)
- Mahsa Alimohammadian
- Surface Chemistry Research Laboratory, Faculty of Chemistry, Iran University of Science and Technology, Tehran, Iran
| | - Saeid Azizian
- Department of Physical Chemistry, Faculty of Chemistry, Bu-Ali Sina University, Hamedan, Iran
| | - Beheshteh Sohrabi
- Surface Chemistry Research Laboratory, Faculty of Chemistry, Iran University of Science and Technology, Tehran, Iran.
| |
Collapse
|
5
|
Luong NT, Boily JF. Water Film-Driven Brucite Nanosheet Growth and Stacking. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2023; 39:11090-11098. [PMID: 37486722 PMCID: PMC10413962 DOI: 10.1021/acs.langmuir.3c01411] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/26/2023] [Revised: 07/11/2023] [Indexed: 07/25/2023]
Abstract
Thin water films that form by the adhesion and condensation of air moisture on minerals can initiate phase transformation reactions with broad implications in nature and technology. We here show important effects of water film coverages on reaction rates and products during the transformation of periclase (MgO) nanocubes to brucite [Mg(OH)2] nanosheets. Using vibrational spectroscopy, we found that the first minutes to hours of Mg(OH)2 growth followed first-order kinetics, with rates scaling with water loadings. Growth was tightly linked to periclase surface hydration and to the formation of a brucite precursor solid, akin to poorly stacked/dislocated nanosheets. These nanosheets were the predominant forms of Mg(OH)2 growth in the 2D-like hydration environments of sub-monolayer water films, which formed below ∼50% relative humidity (RH). From molecular simulations, we infer that reactions may have been facilitated near surface defects where sub-monolayer films preferentially accumulated. In contrast, the 3D-like hydration environment of multilayered water films promoted brucite nanoparticle formation by enhancing Mg(OH)2 nanosheet growth and stacking rates and yields. From the structural similarity of periclase and brucite to other metal (hydr)oxide minerals, this concept of contrasting nanosheet growth should even be applicable for explaining water film-driven mineralogical transformations on other related nanominerals.
Collapse
Affiliation(s)
- N. Tan Luong
- Department of Chemistry, Umeå
University, Umeå SE 901 87, Sweden
| | | |
Collapse
|
6
|
Luong NT, Holmboe M, Boily JF. MgO nanocube hydroxylation by nanometric water films. NANOSCALE 2023. [PMID: 37194306 DOI: 10.1039/d2nr07140a] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Hydrophilic nanosized minerals exposed to air moisture host thin water films that are key drivers of reactions of interest in nature and technology. Water films can trigger irreversible mineralogical transformations, and control chemical fluxes across networks of aggregated nanomaterials. Using X-ray diffraction, vibrational spectroscopy, electron microscopy, and (micro)gravimetry, we tracked water film-driven transformations of periclase (MgO) nanocubes to brucite (Mg(OH)2) nanosheets. We show that three monolayer-thick water films first triggered the nucleation-limited growth of brucite, and that water film loadings continuously increased as newly-formed brucite nanosheets captured air moisture. Small (8 nm-wide) nanocubes were completely converted to brucite under this regime while growth on larger (32 nm-wide) nanocubes transitioned to a diffusion-limited regime when (∼0.9 nm-thick) brucite nanocoatings began hampering the flux of reactive species. We also show that intra- and inter-particle microporosity hosted a hydration network that sustained GPa-level crystallization pressures, compressing interlayer brucite spacing during growth. This was prevalent in aggregated 8 nm wide nanocubes, which formed a maze-like network of slit-shaped pores. By resolving the impact of nanocube size and microporosity on reaction yields and crystallization pressures, this work provides new insight into the study of mineralogical transformations induced by nanometric water films. Our findings can be applied to structurally related minerals important to nature and technology, as well as to advance ideas on crystal growth under nanoconfinement.
Collapse
Affiliation(s)
- N Tan Luong
- Department of Chemistry, Umeå University, SE 901 87 Umeå, Sweden.
| | - Michael Holmboe
- Department of Chemistry, Umeå University, SE 901 87 Umeå, Sweden.
| | | |
Collapse
|
7
|
Kamaratos M, Giotopoulou Ε, Vlachos D. The interaction mechanism of cesium with water on the SrTiO3(100) surface at room temperature. REACTION KINETICS MECHANISMS AND CATALYSIS 2022. [DOI: 10.1007/s11144-022-02320-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
AbstractThe interaction of water with cesium on the strontium titanate surface SrTiO3(100), was studied, mainly by means of work function measurements and thermal desorption spectroscopy. The catalytic role of cesium with respect to the dissociation of water on surface was investigated, by applying two different adsorption processes at room temperature (RT): (1) The adsorption of water on the cesium covered surface (sequential adsorption), and (2) the co-adsorption process (simultaneous adsorption) on surface. Based on the results and by adopting the Lewis acid–base model, we conclude that during the sequential adsorption the water molecules are mostly adsorbs non-dissociatively on surface, without oxidizing the alkaline overlayer. This seems to be due, first to the strong interaction between the alkaline adatoms and the substrate, and secondly to the limited maximum pre-deposited amount of cesium (≤ 0.45 ML). Instead, water dissociation appears to merely occur on defective sites of the substrate in accordance with previous studies. For a full cesium layer covered surface, the adsorbed water retracts the metallicity of cesium due to electrostatic interactions. In contrast to the sequential adsorption, during the co-adsorption process the oxidation of cesium takes place above a critical coverage of cesium (≥ 0.45 ML). It appears that the co-adsorbed cesium with water modifies the surface potential providing an effective template for cesium oxide, Cs2O development. Based on that, we suggest a catalytic reaction of water dissociation according to the Langmuir–Hinshelwood mechanism. Finally, we propose atomistic adsorption models for both processes of cesium with water adsorption.
Collapse
|
8
|
Cheng Y, Li RZ, Xu XY, Lu L. Density functional theory study of the reaction between VO− and water. Chem Phys Lett 2022. [DOI: 10.1016/j.cplett.2022.139945] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
|
9
|
Chen L, Han Y, Li W, Zhan X, Wang H, Shi C, Sun Y, Shi H. Removal of Sb(V) from wastewater via siliceous ferrihydrite: Interactions among ferrihydrite, coprecipitated Si, and adsorbed Sb(V). CHEMOSPHERE 2022; 291:133043. [PMID: 34826449 DOI: 10.1016/j.chemosphere.2021.133043] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/05/2021] [Revised: 11/18/2021] [Accepted: 11/21/2021] [Indexed: 06/13/2023]
Abstract
Although ferrihydrite (Fh) exhibits good Sb(V) adsorption behavior, the instability of its amorphous structure limits its engineering applications. In this study, siliceous ferrihydrite (SiFh) was prepared via coprecipitation to resolve these limitations. X-ray diffraction (XRD), Fourier-transform infrared (FTIR) spectroscopy, X-ray photoelectron spectroscopy (XPS), and SiFh aging tests revealed that the growth of Fh particles covered with Fe-O-Si links was inhibited while maintaining their amorphous structure. Meanwhile, the XRD patterns indicated that SiFh maintained excellent stability after five adsorption-desorption cycles. During the aging process, the added Si decreased the electrostatic interaction between SiFh and Sb(V), which weakened the affinity between Sb(V) and Fh; however, most of the Sb(V) still entered the Fe lattice after seven days of aging, which was favorable for Sb(V) recovery during reutilization. Furthermore, Sb(V) adsorbed from the simulated textile wastewater onto SiFh had the highest adsorption energy (Eads), which meant its unstable inner-sphere complexation on the surface of SiFh. Meanwhile, the presence of SO42-, NO3-, Ca2+, and Mg2+ contributed to Sb(V) outer-sphere adsorption. Both of these factors were conducive to Sb(V) desorption. Hence, SiFh is a promising adsorbent owing to its facile preparation process, stability, and optimal regeneration properties.
Collapse
Affiliation(s)
- Lei Chen
- College of Environment & Resource Sciences, Zhejiang University, Hangzhou, 310058, People's Republic of China
| | - Yu Han
- College of Environment & Resource Sciences, Zhejiang University, Hangzhou, 310058, People's Republic of China
| | - Wei Li
- Hydrochina Huadong Engineering Corporation Limited, Hangzhou, 311122, People's Republic of China
| | - Xiaohui Zhan
- College of Environment & Resource Sciences, Zhejiang University, Hangzhou, 310058, People's Republic of China
| | - He Wang
- State Grid Zhejiang Electric Power Corporation Research Institute, Hangzhou, 310014, People's Republic of China
| | - Chengchao Shi
- College of Environment & Resource Sciences, Zhejiang University, Hangzhou, 310058, People's Republic of China
| | - Yanping Sun
- College of Environment & Resource Sciences, Zhejiang University, Hangzhou, 310058, People's Republic of China
| | - Huixiang Shi
- College of Environment & Resource Sciences, Zhejiang University, Hangzhou, 310058, People's Republic of China.
| |
Collapse
|
10
|
Sun Z, Rodríguez-Fernández J, Lauritsen JV. Water dissociation on mixed Co-Fe oxide bilayer nanoislands on Au(111). JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2022; 34:164004. [PMID: 35108698 DOI: 10.1088/1361-648x/ac513a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/16/2021] [Accepted: 02/02/2022] [Indexed: 06/14/2023]
Abstract
We investigate the hydroxylation behaviour of mixed Co-Fe oxide nanoislands synthesized on a Au(111) surface under exposure to water vapour at vacuum conditions. The pure Co and Fe bilayer oxides both become hydroxylated by water exposure in vacuum conditions, albeit to a very different extent. It is however an open question how mixed oxides, exposing sites with a mixed coordination to Fe and Co, behave. By forming surface O species with a mixed Fe/Co coordination, we can investigate the nature of such sites. By means of scanning tunnelling microscopy and x-ray photoelectron spectroscopy, we characterize a series of Co-Fe oxides samples with different Fe contents at the atomic scale and observe a scaling of the hydroxylation degree with the amount of Fe inside the Co-Fe oxides. Our results indicate that the Fe dopants within the Co-Fe oxides have opposing effects on edge and basal plane sites modifying the maximum hydroxylation degree of pure cobalt oxide, perturbing the original binding sites of H, releasing the absorbed H or blocking the diffusion pathway of H.
Collapse
Affiliation(s)
- Zhaozong Sun
- Interdisciplinary Nanoscience Center (iNANO), Aarhus University, 8000 Aarhus C, Denmark
| | | | - Jeppe V Lauritsen
- Interdisciplinary Nanoscience Center (iNANO), Aarhus University, 8000 Aarhus C, Denmark
| |
Collapse
|
11
|
Pazniak H, Varezhnikov AS, Kolosov DA, Plugin IA, Vito AD, Glukhova OE, Sheverdyaeva PM, Spasova M, Kaikov I, Kolesnikov EA, Moras P, Bainyashev AM, Solomatin MA, Kiselev I, Wiedwald U, Sysoev VV. 2D Molybdenum Carbide MXenes for Enhanced Selective Detection of Humidity in Air. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2021; 33:e2104878. [PMID: 34601739 DOI: 10.1002/adma.202104878] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/25/2021] [Revised: 09/07/2021] [Indexed: 05/27/2023]
Abstract
2D transition metal carbides and nitrides (MXenes) open up novel opportunities in gas sensing with high sensitivity at room temperature. Herein, 2D Mo2 CTx flakes with high aspect ratio are successfully synthesized. The chemiresistive effect in a sub-µm MXene multilayer for different organic vapors and humidity at 101 -104 ppm in dry air is studied. Reasonably, the low-noise resistance signal allows the detection of H2 O down to 10 ppm. Moreover, humidity suppresses the response of Mo2 CTx to organic analytes due to the blocking of adsorption active sites. By measuring the impedance of MXene layers as a function of ac frequency in the 10-2 -106 Hz range, it is shown that operation principle of the sensor is dominated by resistance change rather than capacitance variations. The sensor transfer function allows to conclude that the Mo2 CTx chemiresistance is mainly originating from electron transport through interflake potential barriers with heights up to 0.2 eV. Density functional theory calculations, elucidating the Mo2 C surface interaction with organic analytes and H2 O, explain the experimental data as an energy shift of the density of states under the analyte's adsorption which induces increasing electrical resistance.
Collapse
Affiliation(s)
- Hanna Pazniak
- Faculty of Physics and Center for Nanointegration Duisburg-Essen, University of Duisburg-Essen, Lotharstr. 1, 47057, Duisburg, Germany
| | - Alexey S Varezhnikov
- Yuri Gagarin State Technical University of Saratov, Politekhnicheskaya str. 77, Saratov, 410054, Russia
| | - Dmitry A Kolosov
- Department of Physics, Saratov State University, Astrakhanskaya str. 83, Saratov, 410012, Russia
| | - Ilya A Plugin
- Yuri Gagarin State Technical University of Saratov, Politekhnicheskaya str. 77, Saratov, 410054, Russia
| | - Alessia Di Vito
- Department of Electronic Engineering, University of Rome Tor Vergata, Via Cracovia, 50, Roma, 00133, Italy
| | - Olga E Glukhova
- Department of Physics, Saratov State University, Astrakhanskaya str. 83, Saratov, 410012, Russia
- Laboratory of Biomedical Nanotechnology, I. M. Sechenov First Moscow State Medical University, Trubetskaya str. 8-2, Moscow, 119991, Russia
| | | | - Marina Spasova
- Faculty of Physics and Center for Nanointegration Duisburg-Essen, University of Duisburg-Essen, Lotharstr. 1, 47057, Duisburg, Germany
| | - Igor Kaikov
- Breitmeier Messtechnik GmbH, Englerstr. 27, 76275, Ettlingen, Germany
| | - Evgeny A Kolesnikov
- National University of Science & Technology (NUST) MISIS, Leninskiy Prospekt 4, Moscow, 119049, Russia
| | - Paolo Moras
- Institute of Structure of Matter (ISM-CNR), SS 14 Km, Trieste, 34149, Italy
| | - Alexey M Bainyashev
- Yuri Gagarin State Technical University of Saratov, Politekhnicheskaya str. 77, Saratov, 410054, Russia
| | - Maksim A Solomatin
- Yuri Gagarin State Technical University of Saratov, Politekhnicheskaya str. 77, Saratov, 410054, Russia
| | - Ilia Kiselev
- Breitmeier Messtechnik GmbH, Englerstr. 27, 76275, Ettlingen, Germany
| | - Ulf Wiedwald
- Faculty of Physics and Center for Nanointegration Duisburg-Essen, University of Duisburg-Essen, Lotharstr. 1, 47057, Duisburg, Germany
| | - Victor V Sysoev
- Yuri Gagarin State Technical University of Saratov, Politekhnicheskaya str. 77, Saratov, 410054, Russia
| |
Collapse
|
12
|
Elucidation of Gram-Positive Bacterial Iron(III) Reduction for Kaolinite Clay Refinement. Molecules 2021; 26:molecules26113084. [PMID: 34064160 PMCID: PMC8196777 DOI: 10.3390/molecules26113084] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2021] [Revised: 05/11/2021] [Accepted: 05/18/2021] [Indexed: 11/29/2022] Open
Abstract
Recently, microbial-based iron reduction has been considered as a viable alternative to typical chemical-based treatments. The iron reduction is an important process in kaolin refining, where iron-bearing impurities in kaolin clay affects the whiteness, refractory properties, and its commercial value. In recent years, Gram-negative bacteria has been in the center stage of iron reduction research, whereas little is known about the potential use of Gram-positive bacteria to refine kaolin clay. In this study, we investigated the ferric reducing capabilities of five microbes by manipulating the microbial growth conditions. Out of the five, we discovered that Bacillus cereus and Staphylococcus aureus outperformed the other microbes under nitrogen-rich media. Through the biochemical changes and the microbial behavior, we mapped the hypothetical pathway leading to the iron reduction cellular properties, and found that the iron reduction properties of these Gram-positive bacteria rely heavily on the media composition. The media composition results in increased basification of the media that is a prerequisite for the cellular reduction of ferric ions. Further, these changes impact the formation of biofilm, suggesting that the cellular interaction for the iron(III)oxide reduction is not solely reliant on the formation of biofilms. This article reveals the potential development of Gram-positive microbes in facilitating the microbial-based removal of metal contaminants from clays or ores. Further studies to elucidate the corresponding pathways would be crucial for the further development of the field.
Collapse
|
13
|
Zhao S, Lin L, Huang W, Zhang R, Wang D, Mu R, Fu Q, Bao X. Design of Lewis Pairs via Interface Engineering of Oxide-Metal Composite Catalyst for Water Activation. J Phys Chem Lett 2021; 12:1443-1452. [PMID: 33523659 DOI: 10.1021/acs.jpclett.0c03760] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
The rational design and controlled construction of active centers remain grand challenges in heterogeneous catalysis, in particular for oxide catalysts with complex surface and interface structures. This work describes a facile way in the design of highly active Ni-O Lewis pairs for water activation where Ni and O sites act as Lewis acid and base, respectively. Surface science experiments indicate that dissociative adsorption of water occurs at edges of NiOx nanoislands grown on Au(111) and NiOx-Ni interfaces formed by further depositing metallic Ni layers along the edges of NiOx nanoislands. Enhanced activity of Ni-O Lewis pairs at the NiOx-Ni interface has been demonstrated by theoretical calculations, which are attributed to the higher Lewis acidity of metallic Ni sites and synergy of the metal and oxide components. Moreover, proton can migrate away from the NiOx-Ni interface and refresh the O base sites, leading to further hydroxylation of the neighboring Ni acid sites.
Collapse
Affiliation(s)
- Siqin Zhao
- State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Le Lin
- State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China
- School of Physical Science and Technology, ShanghaiTech University, Shanghai 201210, China
| | - Wugen Huang
- State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Rankun Zhang
- State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China
- Zhang Dayu School of Chemistry, Dalian University of Technology, Dalian 116024, China
| | - Dongqing Wang
- State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Rentao Mu
- State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China
| | - Qiang Fu
- State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China
| | - Xinhe Bao
- State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China
- Department of Chemical Physics, University of Science and Technology of China, Hefei 230026, China
| |
Collapse
|
14
|
Li J, Joseph T, Ghorbani-Asl M, Kolekar S, Krasheninnikov AV, Batzill M. Mirror twin boundaries in MoSe 2 monolayers as one dimensional nanotemplates for selective water adsorption. NANOSCALE 2021; 13:1038-1047. [PMID: 33393546 DOI: 10.1039/d0nr08345c] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Water adsorption on transition metal dichalcogenides and other 2D materials is generally governed by weak van der Waals interactions. This results in a hydrophobic character of the basal planes, and defects may play a significant role in water adsorption and water cluster nucleation. However, there is a lack of detailed experimental investigations on water adsorption on defective 2D materials. Here, by combining low-temperature scanning tunneling microscopy (STM) experiments and density functional theory (DFT) calculations, we study in that context the well-defined mirror twin boundary (MTB) networks separating mirror-grains in 2D MoSe2. These MTBs are dangling bond-free extended crystal modifications with metallic electronic states embedded in the 2D semiconducting matrix of MoSe2. Our DFT calculations indicate that molecular water also interacts similarly weak with these MTBs as with the defect-free basal plane of MoSe2. However, in low temperature STM experiments, nanoscopic water structures are observed that selectively decorate the MTB network. This localized adsorption of water is facilitated by functionalization of the MTBs by hydroxyls formed by dissociated water. Hydroxyls may form by dissociating of water at undercoordinated defects or adsorbing of radicals from the gas phase in the UHV chamber. Our DFT analysis indicates that the metallic MTBs adsorb these radicals much stronger than on the basal plane due to charge transfer from the metallic states into the molecular orbitals of the OH groups. Once the MTBs are functionalized with hydroxyls, molecular water can attach to them, forming water channels along the MTBs. This study demonstrates the role metallic defect states play in the adsorption of water even in the absence of unsaturated bonds that have been so far considered to be crucial for adsorption of hydroxyls or water.
Collapse
Affiliation(s)
- Jingfeng Li
- Department of Physics, University of South Florida, Tampa, FL 33647, USA.
| | - Thomas Joseph
- Helmholtz-Zentrum Dresden-Rossendorf, Institute of Ion Beam Physics and Materials Research, 01328 Dresden, Germany
| | - Mahdi Ghorbani-Asl
- Helmholtz-Zentrum Dresden-Rossendorf, Institute of Ion Beam Physics and Materials Research, 01328 Dresden, Germany
| | - Sadhu Kolekar
- Department of Physics, University of South Florida, Tampa, FL 33647, USA.
| | - Arkady V Krasheninnikov
- Helmholtz-Zentrum Dresden-Rossendorf, Institute of Ion Beam Physics and Materials Research, 01328 Dresden, Germany and Department of Applied Physics, Aalto University, P.O. Box 11100, 00076 Aalto, Finland
| | - Matthias Batzill
- Department of Physics, University of South Florida, Tampa, FL 33647, USA.
| |
Collapse
|
15
|
Han L, Li B, Tao S, An J, Fu B, Han Y, Li W, Li X, Peng S, Yin T. Graphene oxide-induced formation of a boron-doped iron oxide shell on the surface of NZVI for enhancing nitrate removal. CHEMOSPHERE 2020; 252:126496. [PMID: 32203782 DOI: 10.1016/j.chemosphere.2020.126496] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/27/2019] [Revised: 03/12/2020] [Accepted: 03/13/2020] [Indexed: 06/10/2023]
Abstract
The surface products have a significant influence on the reactivity of zero-valent iron-based materials. Although the enhancing effect of graphene on the reactivity of nanoscale zero-valent iron (NZVI)/graphene composites have been confirmed, the effect of graphene on the formation of surface products of NZVI is not well understood. In order to assess the effect of graphene on the structural of the outer iron oxide layers of NZVI, the NZVI was pre-oxidized by graphene oxide (ONZVI-GO). Compared with the NZVI oxidized by O2 (ONZVI-O2), ONZVI-GO was shown to be effective at NO3- removal with a high efficiency over a wide range of initial pH values. The results from characterization showed that GO could induce the formation of a tight iron oxide shell with dense spinel structures. The boron introduced during the preparation of NZVI was doped into iron oxides on the surface of ONZVI-GO. The B-O in adsorbed borate was transformed to B-B/B-Fe in the lattice structure of iron oxides, causing the formation of highly electron-deficient Lewis acid sites on the surface of ONZVI-GO, which could effectively gather NO3- and OH-, leading to the higher efficiency removal of NO3- than ONZVI-O2 over a wide range of initial pH values. This study provides new insight into the interaction between graphene and the surface species of NZVI.
Collapse
Affiliation(s)
- Luchao Han
- Sino-French Institute for Earth System Science, Laboratory for Earth Surface Processes, College of Urban and Environmental Sciences, Peking University, Beijing, 100871, China
| | - Bengang Li
- Sino-French Institute for Earth System Science, Laboratory for Earth Surface Processes, College of Urban and Environmental Sciences, Peking University, Beijing, 100871, China; Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application, Nanjing, 210023, China.
| | - Shu Tao
- Sino-French Institute for Earth System Science, Laboratory for Earth Surface Processes, College of Urban and Environmental Sciences, Peking University, Beijing, 100871, China
| | - Jie An
- Sino-French Institute for Earth System Science, Laboratory for Earth Surface Processes, College of Urban and Environmental Sciences, Peking University, Beijing, 100871, China
| | - Bo Fu
- Sino-French Institute for Earth System Science, Laboratory for Earth Surface Processes, College of Urban and Environmental Sciences, Peking University, Beijing, 100871, China
| | - Yunman Han
- Sino-French Institute for Earth System Science, Laboratory for Earth Surface Processes, College of Urban and Environmental Sciences, Peking University, Beijing, 100871, China
| | - Wei Li
- Sino-French Institute for Earth System Science, Laboratory for Earth Surface Processes, College of Urban and Environmental Sciences, Peking University, Beijing, 100871, China
| | - Xinyue Li
- Sino-French Institute for Earth System Science, Laboratory for Earth Surface Processes, College of Urban and Environmental Sciences, Peking University, Beijing, 100871, China
| | - Siyuan Peng
- Sino-French Institute for Earth System Science, Laboratory for Earth Surface Processes, College of Urban and Environmental Sciences, Peking University, Beijing, 100871, China
| | - Tianya Yin
- Sino-French Institute for Earth System Science, Laboratory for Earth Surface Processes, College of Urban and Environmental Sciences, Peking University, Beijing, 100871, China
| |
Collapse
|
16
|
Aleskndrany A, Sahin I. The effects of Levothyroxine on the structure and dynamics of DPPC liposome: FTIR and DSC studies. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2020; 1862:183245. [DOI: 10.1016/j.bbamem.2020.183245] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/18/2019] [Revised: 02/12/2020] [Accepted: 02/17/2020] [Indexed: 12/20/2022]
|
17
|
Li Y, Adamsen KC, Lammich L, Lauritsen JV, Wendt S. Atomic-Scale View of the Oxidation and Reduction of Supported Ultrathin FeO Islands. ACS NANO 2019; 13:11632-11641. [PMID: 31513376 DOI: 10.1021/acsnano.9b05470] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
By means of scanning tunneling microscopy (STM) measurements, we studied in situ the oxidation and reduction of FeO bilayer islands on Au(111) by oxygen (O2) and hydrogen (H2), respectively. The FeO islands respond very dynamically toward O2, with the coordinatively unsaturated ferrous (CUF) sites at the island edges being essential for O2 dissociation and O atom incorporation. An STM movie obtained during oxidation reveals how further O2 molecules can dissociate after the consumption of all initially existing CUF sites through the formation of new CUF sites. In contrast, we found that H2 molecules only dissociate when vibrationally excited through the ion gauge and only at the basal plane of FeO islands, implying that the CUF sites are not relevant for H2 dissociation. Our STM results reveal how excess O atoms are incorporated and released in O2 and H2 and thus shed light onto the stability of inverse catalysts during a catalyzed reaction.
Collapse
Affiliation(s)
- Yijia Li
- Interdisciplinary Nanoscience Center (iNANO) and Department of Physics and Astronomy , Aarhus University , DK-8000 Aarhus C , Denmark
| | - Kræn C Adamsen
- Interdisciplinary Nanoscience Center (iNANO) and Department of Physics and Astronomy , Aarhus University , DK-8000 Aarhus C , Denmark
| | - Lutz Lammich
- Interdisciplinary Nanoscience Center (iNANO) and Department of Physics and Astronomy , Aarhus University , DK-8000 Aarhus C , Denmark
| | - Jeppe V Lauritsen
- Interdisciplinary Nanoscience Center (iNANO) and Department of Physics and Astronomy , Aarhus University , DK-8000 Aarhus C , Denmark
| | - Stefan Wendt
- Interdisciplinary Nanoscience Center (iNANO) and Department of Physics and Astronomy , Aarhus University , DK-8000 Aarhus C , Denmark
| |
Collapse
|
18
|
Purification of Fluorescently Derivatized N-Glycans by Magnetic Iron Nanoparticles. NANOMATERIALS 2019; 9:nano9101480. [PMID: 31627435 PMCID: PMC6835309 DOI: 10.3390/nano9101480] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/03/2019] [Revised: 10/14/2019] [Accepted: 10/16/2019] [Indexed: 11/17/2022]
Abstract
A novel glycoanalytical approach was developed in this study for the purification of fluorescently derivatized N-glycans. Polyethylene glycol (PEG) modified iron-nanoparticles were synthetized by the combination of sonochemical treatment and combustion method. The prepared nanomaterials were applied for a systematic clean-up optimization to maximize purification efficiency of 2-AA labelled glycans. PEG 1000 modified iron-oxalate was found to be the most effective for the selective enrichment of serum N-glycans providing high reproducibility. Different acetonitrile percentages for binding and washing steps were also tested to ensure the same relative peak areas compared to the unpurified sample. The generated novel clean-up strategy provides a potential route to use in-house synthetized magnetic nanoparticles for glycan sample preparation.
Collapse
|
19
|
Gleißner R, Creutzburg M, Noei H, Stierle A. Interaction of Water with Graphene/Ir(111) Studied by Vibrational Spectroscopy. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2019; 35:11285-11290. [PMID: 31361486 DOI: 10.1021/acs.langmuir.9b01205] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
Water in confinement exhibits altered properties in molecular arrangement, bonding, and interaction with its neighboring environment, as compared to its bulk counterpart. In this work, periodically arranged D2O nano droplets of ∼1 nm size on top of a graphene/iridium moiré superstructure were investigated by Fourier transform infrared reflection absorption spectroscopy (FT-IRRAS) under ultrahigh vacuum conditions at ∼120 K. The IR bands of D2O clusters differ significantly from those observed for bulk D2O amorphous solid water or crystalline ice phases. Blue-shifted symmetric and asymmetric stretching bands with narrower band widths and modified band intensity ratios were observed, pointing to an enhanced internal order and a reduced nearest neighbor distance. Furthermore, two IR bands of "dangling" deuterium atoms were detected originating from threefold coordinated water molecules at the surface of the clusters and at their interface to the graphene layer. The latter arose only with the transition from the water clusters to an amorphous solid water layer. We propose that upon coalescence, opposing local dipoles trigger a hydrogen bond rearrangement at the interface. Our results represent a first step toward an atomistic understanding of water in confinement.
Collapse
Affiliation(s)
- Robert Gleißner
- Deutsches Elektronen-Synchrotron (DESY) , Hamburg D-22607 , Germany
- Fachbereich Physik , Universität Hamburg , Hamburg 20146 , Germany
| | - Marcus Creutzburg
- Deutsches Elektronen-Synchrotron (DESY) , Hamburg D-22607 , Germany
- Fachbereich Physik , Universität Hamburg , Hamburg 20146 , Germany
| | - Heshmat Noei
- Deutsches Elektronen-Synchrotron (DESY) , Hamburg D-22607 , Germany
| | - Andreas Stierle
- Deutsches Elektronen-Synchrotron (DESY) , Hamburg D-22607 , Germany
- Fachbereich Physik , Universität Hamburg , Hamburg 20146 , Germany
| |
Collapse
|
20
|
Thomä SLJ, Krauss SW, Eckardt M, Chater P, Zobel M. Atomic insight into hydration shells around facetted nanoparticles. Nat Commun 2019; 10:995. [PMID: 30824693 PMCID: PMC6397290 DOI: 10.1038/s41467-019-09007-1] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2018] [Accepted: 02/08/2019] [Indexed: 01/10/2023] Open
Abstract
Nanoparticles in solution interact with their surroundings via hydration shells. Although the structure of these shells is used to explain nanoscopic properties, experimental structural insight is still missing. Here we show how to access the hydration shell structures around colloidal nanoparticles in scattering experiments. For this, we synthesize variably functionalized magnetic iron oxide nanoparticle dispersions. Irrespective of the capping agent, we identify three distinct interatomic distances within 2.5 Å from the particle surface which belong to dissociatively and molecularly adsorbed water molecules, based on theoretical predictions. A weaker restructured hydration shell extends up to 15 Å. Our results show that the crystal structure dictates the hydration shell structure. Surprisingly, facets of 7 and 15 nm particles behave like planar surfaces. These findings bridge the large gap between spectroscopic studies on hydrogen bond networks and theoretical advances in solvation science.
Collapse
Affiliation(s)
- Sabrina L J Thomä
- Department of Chemistry, University of Bayreuth, Universitätsstr.30, 95440, Bayreuth, Germany
| | - Sebastian W Krauss
- Department of Chemistry, University of Bayreuth, Universitätsstr.30, 95440, Bayreuth, Germany
| | - Mirco Eckardt
- Department of Chemistry, University of Bayreuth, Universitätsstr.30, 95440, Bayreuth, Germany
| | - Phil Chater
- Diamond Light Source, Harwell Science & Innovation Campus, Didcot, Oxfordshire, OX11 0DE, UK
| | - Mirijam Zobel
- Department of Chemistry, University of Bayreuth, Universitätsstr.30, 95440, Bayreuth, Germany.
| |
Collapse
|
21
|
Daru J, Gupta PK, Marx D. Restricting Solvation to Two Dimensions: Soft Landing of Microsolvated Ions on Inert Surfaces. J Phys Chem Lett 2019; 10:831-835. [PMID: 30707837 DOI: 10.1021/acs.jpclett.8b03801] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
In an effort to scrutinize dimensional restriction effects on finite hydrogen-bonded networks, we deposit ion-doped water clusters by computational soft landing on a chemically inert supported xenon surface. In stark contrast to the much studied metal or metal oxide surfaces, the rare gas surface interacts only rather weakly and nondirectionally with these networks. Surprisingly, the strongly bound Na+-doped networks undergo very significant plastic deformations, whereas the weakly bound Cl- counterparts barely change upon surface deposition. This counterintuitive finding is traced back to the significantly less favorable water-water interactions enforced by the cation, which results in an easier adaption to geometric restrictions, whereas H-bonding stabilizes the anionic clusters.
Collapse
Affiliation(s)
- János Daru
- Lehrstuhl für Theoretische Chemie , Ruhr-Universität Bochum , 44780 Bochum , Germany
| | - Prashant Kumar Gupta
- Lehrstuhl für Theoretische Chemie , Ruhr-Universität Bochum , 44780 Bochum , Germany
| | - Dominik Marx
- Lehrstuhl für Theoretische Chemie , Ruhr-Universität Bochum , 44780 Bochum , Germany
| |
Collapse
|
22
|
Chen Z, Fan T, Zhang Q, He J, Fan H, Sun Y, Yi X, Li J. Interface engineering: Surface hydrophilic regulation of LaFeO3 towards enhanced visible light photocatalytic hydrogen evolution. J Colloid Interface Sci 2019; 536:105-111. [DOI: 10.1016/j.jcis.2018.10.030] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2018] [Revised: 10/09/2018] [Accepted: 10/12/2018] [Indexed: 11/16/2022]
|
23
|
|
24
|
Schwarz M, Faisal F, Mohr S, Hohner C, Werner K, Xu T, Skála T, Tsud N, Prince KC, Matolín V, Lykhach Y, Libuda J. Structure-Dependent Dissociation of Water on Cobalt Oxide. J Phys Chem Lett 2018; 9:2763-2769. [PMID: 29741895 DOI: 10.1021/acs.jpclett.8b01033] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Understanding the correlation between structure and reactivity of oxide surfaces is vital for the rational design of catalytic materials. In this work, we demonstrate the exceptional degree of structure sensitivity of the water dissociation reaction for one of the most important materials in catalysis and electrocatalysis. We studied H2O on two atomically defined cobalt oxide surfaces, CoO(100) and Co3O4(111). Both surfaces are terminated by O2- and Co2+ in different coordination. By infrared reflection absorption spectroscopy and synchrotron radiation photoelectron spectroscopy we show that H2O adsorbs molecularly on CoO(100), while it dissociates and forms very strongly bound OH and partially dissociated (H2O) n(OH) m clusters on Co3O4(111). We rationalize this structure dependence by the coordination number of surface Co2+. Our results show that specific well-ordered cobalt oxide surfaces interact very strongly with H2O whereas others do not. We propose that this structure dependence plays a key role in catalysis with cobalt oxide nanomaterials.
Collapse
Affiliation(s)
- Matthias Schwarz
- Lehrstuhl für Physikalische Chemie II , Friedrich-Alexander-Universität Erlangen-Nürnberg , Egerlandstraße 3 , 91058 Erlangen , Germany
| | - Firas Faisal
- Lehrstuhl für Physikalische Chemie II , Friedrich-Alexander-Universität Erlangen-Nürnberg , Egerlandstraße 3 , 91058 Erlangen , Germany
| | - Susanne Mohr
- Lehrstuhl für Physikalische Chemie II , Friedrich-Alexander-Universität Erlangen-Nürnberg , Egerlandstraße 3 , 91058 Erlangen , Germany
| | - Chantal Hohner
- Lehrstuhl für Physikalische Chemie II , Friedrich-Alexander-Universität Erlangen-Nürnberg , Egerlandstraße 3 , 91058 Erlangen , Germany
| | - Kristin Werner
- Lehrstuhl für Physikalische Chemie II , Friedrich-Alexander-Universität Erlangen-Nürnberg , Egerlandstraße 3 , 91058 Erlangen , Germany
| | - Tao Xu
- Lehrstuhl für Physikalische Chemie II , Friedrich-Alexander-Universität Erlangen-Nürnberg , Egerlandstraße 3 , 91058 Erlangen , Germany
| | - Tomáš Skála
- Department of Surface and Plasma Science , Faculty of Mathematics and Physics, Charles University , V Holešovičkách 2 , 18000 Prague , Czech Republic
| | - Nataliya Tsud
- Department of Surface and Plasma Science , Faculty of Mathematics and Physics, Charles University , V Holešovičkách 2 , 18000 Prague , Czech Republic
| | - Kevin C Prince
- Elettra-Sincrotrone Trieste SCpA , Strada Statale 14, km 163.5 , 34149 Basovizza-Trieste , Italy
| | - Vladimír Matolín
- Department of Surface and Plasma Science , Faculty of Mathematics and Physics, Charles University , V Holešovičkách 2 , 18000 Prague , Czech Republic
| | - Yaroslava Lykhach
- Lehrstuhl für Physikalische Chemie II , Friedrich-Alexander-Universität Erlangen-Nürnberg , Egerlandstraße 3 , 91058 Erlangen , Germany
| | - Jörg Libuda
- Lehrstuhl für Physikalische Chemie II , Friedrich-Alexander-Universität Erlangen-Nürnberg , Egerlandstraße 3 , 91058 Erlangen , Germany
- Erlangen Catalysis Resource Center and Interdisciplinary Center Interface Controlled Processes , Friedrich-Alexander-Universität Erlangen-Nürnberg , 91058 Erlangen , Germany
| |
Collapse
|
25
|
Saavedra J, Pursell CJ, Chandler BD. CO Oxidation Kinetics over Au/TiO2 and Au/Al2O3 Catalysts: Evidence for a Common Water-Assisted Mechanism. J Am Chem Soc 2018; 140:3712-3723. [DOI: 10.1021/jacs.7b12758] [Citation(s) in RCA: 75] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Affiliation(s)
- Johnny Saavedra
- Department of Chemistry, Trinity University, San Antonio, Texas 78212-7200, United States
- Pacific Northwest National Laboratory Institute for Integrated Catalysis, Richland, Washington 99352, United States
| | - Christopher J. Pursell
- Department of Chemistry, Trinity University, San Antonio, Texas 78212-7200, United States
| | - Bert D. Chandler
- Department of Chemistry, Trinity University, San Antonio, Texas 78212-7200, United States
| |
Collapse
|
26
|
Weakly perturbative imaging of interfacial water with submolecular resolution by atomic force microscopy. Nat Commun 2018; 9:122. [PMID: 29317638 PMCID: PMC5760619 DOI: 10.1038/s41467-017-02635-5] [Citation(s) in RCA: 62] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2017] [Accepted: 12/15/2017] [Indexed: 11/11/2022] Open
Abstract
Scanning probe microscopy has been extensively applied to probe interfacial water in many interdisciplinary fields but the disturbance of the probes on the hydrogen-bonding structure of water has remained an intractable problem. Here, we report submolecular-resolution imaging of the water clusters on a NaCl(001) surface within the nearly noninvasive region by a qPlus-based noncontact atomic force microscopy. Comparison with theoretical simulations reveals that the key lies in probing the weak high-order electrostatic force between the quadrupole-like CO-terminated tip and the polar water molecules at large tip–water distances. This interaction allows the imaging and structural determination of the weakly bonded water clusters and even of their metastable states with negligible disturbance. This work may open an avenue for studying the intrinsic structure and dynamics of ice or water on surfaces, ion hydration, and biological water with atomic precision. Scanning probe microscopy has been extensively applied to probe interfacial water but the probes tend to disturb the structure of water easily. Here, the authors report submolecular-resolution imaging of water clusters within the nearly non-invasive region by qPlus noncontact atomic force microscopy.
Collapse
|
27
|
Tran-Thuy TM, Chen CC, Lin SD. Spectroscopic Studies of How Moisture Enhances CO Oxidation over Au/BN at Ambient Temperature. ACS Catal 2017. [DOI: 10.1021/acscatal.7b01374] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Tuyet-Mai Tran-Thuy
- Department of Chemical Engineering, National Taiwan University of Science and Technology, Taipei 106, Taiwan
| | - Chin-Chih Chen
- Department of Chemical Engineering, National Taiwan University of Science and Technology, Taipei 106, Taiwan
| | - Shawn D. Lin
- Department of Chemical Engineering, National Taiwan University of Science and Technology, Taipei 106, Taiwan
| |
Collapse
|
28
|
Guo J, Bian K, Lin Z, Jiang Y. Perspective: Structure and dynamics of water at surfaces probed by scanning tunneling microscopy and spectroscopy. J Chem Phys 2017; 145:160901. [PMID: 27802647 DOI: 10.1063/1.4964668] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The detailed and precise understanding of water-solid interaction largely relies on the development of atomic-scale experimental techniques, among which scanning tunneling microscopy (STM) has proven to be a noteworthy example. In this perspective, we review the recent advances of STM techniques in imaging, spectroscopy, and manipulation of water molecules. We discuss how those newly developed techniques are applied to probe the structure and dynamics of water at solid surfaces with single-molecule and even submolecular resolution, paying particular attention to the ability of accessing the degree of freedom of hydrogen. In the end, we present an outlook on the directions of future STM studies of water-solid interfaces as well as the challenges faced by this field. Some new scanning probe techniques beyond STM are also envisaged.
Collapse
Affiliation(s)
- Jing Guo
- International Center for Quantum Materials, School of Physics, Peking University, Beijing 100871, People's Republic of China
| | - Ke Bian
- International Center for Quantum Materials, School of Physics, Peking University, Beijing 100871, People's Republic of China
| | - Zeren Lin
- International Center for Quantum Materials, School of Physics, Peking University, Beijing 100871, People's Republic of China
| | - Ying Jiang
- International Center for Quantum Materials, School of Physics, Peking University, Beijing 100871, People's Republic of China
| |
Collapse
|
29
|
Fester J, García-Melchor M, Walton AS, Bajdich M, Li Z, Lammich L, Vojvodic A, Lauritsen JV. Edge reactivity and water-assisted dissociation on cobalt oxide nanoislands. Nat Commun 2017; 8:14169. [PMID: 28134335 PMCID: PMC5290272 DOI: 10.1038/ncomms14169] [Citation(s) in RCA: 98] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2016] [Accepted: 11/30/2016] [Indexed: 11/30/2022] Open
Abstract
Transition metal oxides show great promise as Earth-abundant catalysts for the oxygen evolution reaction in electrochemical water splitting. However, progress in the development of highly active oxide nanostructures is hampered by a lack of knowledge of the location and nature of the active sites. Here we show, through atom-resolved scanning tunnelling microscopy, X-ray spectroscopy and computational modelling, how hydroxyls form from water dissociation at under coordinated cobalt edge sites of cobalt oxide nanoislands. Surprisingly, we find that an additional water molecule acts to promote all the elementary steps of the dissociation process and subsequent hydrogen migration, revealing the important assisting role of a water molecule in its own dissociation process on a metal oxide. Inspired by the experimental findings, we theoretically model the oxygen evolution reaction activity of cobalt oxide nanoislands and show that the nanoparticle metal edges also display favourable adsorption energetics for water oxidation under electrochemical conditions.
Collapse
Affiliation(s)
- J. Fester
- Interdisciplinary Nanoscience Center, Aarhus University, DK-8000 Aarhus C, Denmark
| | - M. García-Melchor
- Chemical Engineering and SLAC National Accelerator Laboratory, Stanford University, Stanford, California 94025, USA
- School of Chemistry, Trinity College Dublin, Dublin 2, Ireland
| | - A. S. Walton
- School of Chemistry, University of Manchester, Manchester M13 9PL, UK
| | - M. Bajdich
- Chemical Engineering and SLAC National Accelerator Laboratory, Stanford University, Stanford, California 94025, USA
| | - Z. Li
- Department of Physics and Astronomy, Institute for Storage Ring Facilities, Aarhus, DK-8000 Aarhus C, Denmark
| | - L. Lammich
- Interdisciplinary Nanoscience Center, Aarhus University, DK-8000 Aarhus C, Denmark
| | - A. Vojvodic
- Department of Chemical and Biomolecular Engineering, University of Pennsylvania, 220 South 33rd Street 311A Towne Building Philadelphia Pennsylvania, 19104, USA
| | - J. V. Lauritsen
- Interdisciplinary Nanoscience Center, Aarhus University, DK-8000 Aarhus C, Denmark
| |
Collapse
|
30
|
Farnesi Camellone M, Negreiros Ribeiro F, Szabová L, Tateyama Y, Fabris S. Catalytic Proton Dynamics at the Water/Solid Interface of Ceria-Supported Pt Clusters. J Am Chem Soc 2016; 138:11560-7. [DOI: 10.1021/jacs.6b03446] [Citation(s) in RCA: 57] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- Matteo Farnesi Camellone
- CNR-IOM
DEMOCRITOS, Istituto Officina dei Materiali, Consiglio Nazionale delle Ricerche, Via Bonomea 265, 34136 Trieste, Italy
| | - Fabio Negreiros Ribeiro
- CNR-IOM
DEMOCRITOS, Istituto Officina dei Materiali, Consiglio Nazionale delle Ricerche, Via Bonomea 265, 34136 Trieste, Italy
| | - Lucie Szabová
- Center
for Green Research on Energy and Environmental Materials (GREEN), National Institute for Materials Science (NIMS), 1-1 Namiki, Tsukuba, Ibaraki 305-0044, Japan
| | - Yoshitaka Tateyama
- Center
for Green Research on Energy and Environmental Materials (GREEN), National Institute for Materials Science (NIMS), 1-1 Namiki, Tsukuba, Ibaraki 305-0044, Japan
| | - Stefano Fabris
- CNR-IOM
DEMOCRITOS, Istituto Officina dei Materiali, Consiglio Nazionale delle Ricerche, Via Bonomea 265, 34136 Trieste, Italy
- SISSA, Scuola Internazionale Superiore di Studi Avanzati, Via Bonomea 265, 34136 Trieste, Italy
| |
Collapse
|
31
|
Merte LR, Heard CJ, Zhang F, Choi J, Shipilin M, Gustafson J, Weaver JF, Grönbeck H, Lundgren E. Tuning the Reactivity of Ultrathin Oxides: NO Adsorption on Monolayer FeO(111). Angew Chem Int Ed Engl 2016. [DOI: 10.1002/ange.201601647] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Lindsay R. Merte
- Division of Synchrotron Radiation Research Lund University 22100 Lund Sweden
| | - Christopher J. Heard
- Department of Physics and Competence Centre for Catalysis Chalmers University of Technology 41296 Göteborg Sweden
| | - Feng Zhang
- Department of Chemical Engineering University of Florida Gainesville FL 32611 USA
| | - Juhee Choi
- Department of Chemical Engineering University of Florida Gainesville FL 32611 USA
| | - Mikhail Shipilin
- Division of Synchrotron Radiation Research Lund University 22100 Lund Sweden
| | - Johan Gustafson
- Division of Synchrotron Radiation Research Lund University 22100 Lund Sweden
| | - Jason F. Weaver
- Department of Chemical Engineering University of Florida Gainesville FL 32611 USA
| | - Henrik Grönbeck
- Department of Physics and Competence Centre for Catalysis Chalmers University of Technology 41296 Göteborg Sweden
| | - Edvin Lundgren
- Division of Synchrotron Radiation Research Lund University 22100 Lund Sweden
| |
Collapse
|
32
|
Merte LR, Heard CJ, Zhang F, Choi J, Shipilin M, Gustafson J, Weaver JF, Grönbeck H, Lundgren E. Tuning the Reactivity of Ultrathin Oxides: NO Adsorption on Monolayer FeO(111). Angew Chem Int Ed Engl 2016; 55:9267-71. [DOI: 10.1002/anie.201601647] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2016] [Revised: 04/20/2016] [Indexed: 11/06/2022]
Affiliation(s)
- Lindsay R. Merte
- Division of Synchrotron Radiation Research Lund University 22100 Lund Sweden
| | - Christopher J. Heard
- Department of Physics and Competence Centre for Catalysis Chalmers University of Technology 41296 Göteborg Sweden
| | - Feng Zhang
- Department of Chemical Engineering University of Florida Gainesville FL 32611 USA
| | - Juhee Choi
- Department of Chemical Engineering University of Florida Gainesville FL 32611 USA
| | - Mikhail Shipilin
- Division of Synchrotron Radiation Research Lund University 22100 Lund Sweden
| | - Johan Gustafson
- Division of Synchrotron Radiation Research Lund University 22100 Lund Sweden
| | - Jason F. Weaver
- Department of Chemical Engineering University of Florida Gainesville FL 32611 USA
| | - Henrik Grönbeck
- Department of Physics and Competence Centre for Catalysis Chalmers University of Technology 41296 Göteborg Sweden
| | - Edvin Lundgren
- Division of Synchrotron Radiation Research Lund University 22100 Lund Sweden
| |
Collapse
|
33
|
Chang CR, Huang ZQ, Li J. The promotional role of water in heterogeneous catalysis: mechanism insights from computational modeling. WILEY INTERDISCIPLINARY REVIEWS-COMPUTATIONAL MOLECULAR SCIENCE 2016. [DOI: 10.1002/wcms.1272] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Affiliation(s)
- Chun-Ran Chang
- Institute of Industrial Catalysis, School of Chemical Engineering and Technology; Xi'an Jiaotong University; Xi'an China
- Department of Chemistry and Key Laboratory of Organic Optoelectronics and Molecular Engineering of Ministry of Education; Tsinghua University; Beijing China
| | - Zheng-Qing Huang
- Institute of Industrial Catalysis, School of Chemical Engineering and Technology; Xi'an Jiaotong University; Xi'an China
| | - Jun Li
- Department of Chemistry and Key Laboratory of Organic Optoelectronics and Molecular Engineering of Ministry of Education; Tsinghua University; Beijing China
| |
Collapse
|
34
|
Carchini G, García-Melchor M, Łodziana Z, López N. Understanding and Tuning the Intrinsic Hydrophobicity of Rare-Earth Oxides: A DFT+U Study. ACS APPLIED MATERIALS & INTERFACES 2016; 8:152-160. [PMID: 26652180 DOI: 10.1021/acsami.5b07905] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Rare-earth oxides (REOs) possess a remarkable intrinsic hydrophobicity, making them candidates for a myriad of applications. Although the superhydrophobicity of REOs has been explored experimentally, the atomistic details of the structure at the oxide-water interface are still not well understood. In this work, we report a density functional theory study of the interaction between water and CeO2, Nd2O3, and α-Al2O3 to explain their different wettability. The wetting of the metal oxide surface is controlled by geometric and electronic factors. While the electronic term is related to the acid-base properties of the surface layer, the geometric factor depends on the matching between adsorption sites and oxygen atoms from the hexagonal water network. For all the metal oxides considered here, water dissociation is confined to the first oxide-water layer. Hydroxyl groups on α-Al2O3 are responsible for the strong oxide-water interaction, and thus, both Al- and hydroxyl-terminated wet. On CeO2, the intrinsic hydrophobicity of the clean surface disappears when lattice hydroxyl groups (created by the reaction of water with oxygen vacancies) are present as they dominate the interaction and drive wetting. Therefore, hydroxyls may convert a intrinsic nonwetting surface into a wetting one. Finally, we also report that surface modifications, like cation substitution, do not change the acid-base character of the surface, and thus they show the same nonwetting properties as native CeO2 or Nd2O3.
Collapse
Affiliation(s)
- Giuliano Carchini
- ICIQ - Institute of Chemical Research of Catalonia, The Barcelona Institute of Science and Technology, Av. Països Catalans 16, 43007 Tarragona, Spain
| | - Max García-Melchor
- SUNCAT Center for Interface Science and Catalysis, SLAC National Accelerator Laboratory , Menlo Park, California 94025, United States
| | - Zbigniew Łodziana
- Institute of Nuclear Physics, Polish Academy of Sciences , ulica Radzikowskiego 152, PL-31-342 Krakow, Poland
| | - Núria López
- ICIQ - Institute of Chemical Research of Catalonia , Av. Països Catalans 16, 43007 Tarragona, Spain
| |
Collapse
|
35
|
|
36
|
Abstract
The adsorption and reactions of water on surfaces has attracted great interest, as water is involved in many physical and chemical processes at interfaces. On metal surfaces, the adsorption energy of water is comparable to the hydrogen bond strength in water. Therefore, the delicate balance between the water-water and the water-metal interaction strength determines the stability of water structures. In such systems, kinetic effects play an important role and many metastable states can form with long lifetimes, such that the most stable state may not reached. This has led to difficulties in the theoretical prediction of water structures as well as to some controversial results. The direct imaging using scanning tunneling microscopy (STM) in ultrahigh vacuum at low temperatures offers a reliable means of understanding the local structure and reaction of water molecules, in particular when interpreted in conjunction with density functional theory calculations. In this Account, a selection of recent STM results on the water adsorption and dissociation on close-packed metal surfaces is reviewed, with a particular focus on Ru(0001). The Ru(0001) surface is one where water adsorbs intact in a metastable state at low temperatures and where partially dissociated layers are formed at temperatures above ∼150 K. First, we will describe the structure of intact water clusters starting with the monomer up to the monolayer. We show that icelike wetting layers do not occur on close-packed metal surfaces but instead hydrogen bonded layers in the form of a mixture of pentagonal, hexagonal, and heptagonal molecular rings are observed. Second, we will discuss the dissociation mechanism of water on Ru(0001). We demonstrate that water adsorption changes from dissociative to molecular as a function of the oxygen preadsorbed on Ru. Finally, we briefly review recent STM experiments on bulk ice (Ih and Ic) and water adsorption on insulating thin films. We conclude with an outlook illustrating the manipulation capabilities of STM in respect to probe the proton and hydrogen dynamics in water clusters.
Collapse
Affiliation(s)
- Sabine Maier
- Department
of Physics, University of Erlangen-Nürnberg, 91058 Erlangen, Germany
| | - Miquel Salmeron
- Materials
Sciences Division, Lawrence Berkeley National Laboratory, University of California, Berkeley, California 94720, United States
- Materials
Science and Engineering Department, University of California, Berkeley, California 94720, United States
| |
Collapse
|
37
|
Mezour MA, Perepichka II, Ivasenko O, Lennox RB, Perepichka DF. Tridentate benzylthiols on Au(111): control of self-assembly geometry. NANOSCALE 2015; 7:5014-5022. [PMID: 25695677 DOI: 10.1039/c4nr07207c] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
A set of hexasubstituted benzene derivatives with three thiol groups in the 1, 3, 5 positions and varied aliphatic substituents in the 2, 4, 6 positions (Me3-BTMT, Et3-BTMT, ODe3-BTMT) has been synthesized and self-assembled on Au(111). The resulting self-assembled monolayers (SAMs) are characterized by scanning tunneling microscopy (STM), X-ray photoelectron spectroscopy (XPS), and electrochemistry. The molecular orientation and long-range order are affected by the “gear effect” of the hexasubstituted benzene ring and van der Waals interactions between the physisorbed alkyl chains drive. Me3-BTMT adopts a standing up orientation which results in the highest molecular surface density but also the lowest degree of chemisorption (1 to 2 Au–S bonds per molecule). In contrast, Et3-BTMT favors a lying down orientation with a greater number of surface-bonded thiol groups (2 to 3) per molecule, associated with the peculiar geometry of this molecule. Finally, ODe3-BTMT adsorbs mainly in a lying down orientation, forming the SAM with the highest degree of chemisorption (all thiol groups are gold-bonded) and the lowest molecular areal density.
Collapse
Affiliation(s)
- Mohamed A Mezour
- Department of Chemistry and Centre for Self-Assembled Chemical Structures, McGill University, 801 Sherbrooke St. West, Montreal (QC) H3A 0B8, Canada.
| | | | | | | | | |
Collapse
|
38
|
Cattelan M, Peng GW, Cavaliere E, Artiglia L, Barinov A, Roling LT, Favaro M, Píš I, Nappini S, Magnano E, Bondino F, Gavioli L, Agnoli S, Mavrikakis M, Granozzi G. The nature of the Fe-graphene interface at the nanometer level. NANOSCALE 2015; 7:2450-2460. [PMID: 25565421 DOI: 10.1039/c4nr04956j] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
The emerging fields of graphene-based magnetic and spintronic devices require a deep understanding of the interface between graphene and ferromagnetic metals. This paper reports a detailed investigation at the nanometer level of the Fe-graphene interface carried out by angle-resolved photoemission, high-resolution photoemission from core levels, near edge X-ray absorption fine structure, scanning tunnelling microscopy and spin polarized density functional theory calculations. Quasi-free-standing graphene was grown on Pt(111), and the iron film was either deposited atop or intercalated beneath graphene. Calculations and experimental results show that iron strongly modifies the graphene band structure and lifts its π band spin degeneracy.
Collapse
Affiliation(s)
- M Cattelan
- Department of Chemical Sciences, University of Padova, via Marzolo 1, I-35131 Padova, Italy.
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
39
|
Jin Y, Sun G, Xiong F, Ding L, Huang W. Hydrogen Spillover Enhanced Hydroxyl Formation and Catalytic Activity Toward CO Oxidation at the Metal/Oxide Interface. Chemistry 2015; 21:4252-6. [DOI: 10.1002/chem.201406644] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2014] [Indexed: 11/08/2022]
|
40
|
Huang L, Gubbins KE, Li L, Lu X. Water on titanium dioxide surface: a revisiting by reactive molecular dynamics simulations. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2014; 30:14832-14840. [PMID: 25423593 DOI: 10.1021/la5037426] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
The behavior of surface water, especially the adsorption and dissociation characteristics, is a key to understanding and promoting photocatalytic and biomedical applications of titanium dioxide materials. Using molecular dynamics simulations with the ReaxFF force field, we study the interactions between water and five different TiO2 surfaces that are of interest to both experiments and theoretical calculations. The results show that TiO2 surfaces demonstrate different reactivities for water dissociation [rutile (011) > TiO2-B (100) > anatase (001) > rutile (110)], and there is no water dissociation observed on the TiO2-B (001) surface. The simulations also reveal that the water dissociation and the TiO2 surface chemistry change, and the new surface Ti-OH and O-H functional groups affect the orientation of other near-surface water molecules. On the reactive surface, such as the rutile (110) surface, water dissociated and formed new Ti-OH and O-H bonds on the surface. Those functional groups enhanced the hydrogen bond networking with the near-surface water molecules and their configurations. On the nonreactive TiO2-B (001) surface where no molecular or dissociative water adsorption is observed, near-surface water can also form hydrogen bonds with surface oxygen atoms of TiO2, but their distance to the surface is longer than that on the rutile (011) surface.
Collapse
Affiliation(s)
- Liangliang Huang
- School of Chemical, Biological and Materials Engineering, University of Oklahoma , Norman, Oklahoma 73019, United States
| | | | | | | |
Collapse
|
41
|
Yang M, Li S, Wang Y, Herron JA, Xu Y, Allard LF, Lee S, Huang J, Mavrikakis M, Flytzani-Stephanopoulos M. Catalytically active Au-O(OH)x-species stabilized by alkali ions on zeolites and mesoporous oxides. Science 2014; 346:1498-501. [PMID: 25431492 DOI: 10.1126/science.1260526] [Citation(s) in RCA: 375] [Impact Index Per Article: 37.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
We report that the addition of alkali ions (sodium or potassium) to gold on KLTL-zeolite and mesoporous MCM-41 silica stabilizes mononuclear gold in Au-O(OH)x-(Na or K) ensembles. This single-site gold species is active for the low-temperature (<200°C) water-gas shift (WGS) reaction. Unexpectedly, gold is thus similar to platinum in creating -O linkages with more than eight alkali ions and establishing an active site on various supports. The intrinsic activity of the single-site gold species is the same on irreducible supports as on reducible ceria, iron oxide, and titania supports, apparently all sharing a common, similarly structured gold active site. This finding paves the way for using earth-abundant supports to disperse and stabilize precious metal atoms with alkali additives for the WGS and potentially other fuel-processing reactions.
Collapse
Affiliation(s)
- Ming Yang
- Department of Chemical and Biological Engineering, Tufts University, MA 02155, USA
| | - Sha Li
- Department of Chemical and Biological Engineering, University of Wisconsin-Madison, WI 53706, USA
| | - Yuan Wang
- Department of Chemical and Biological Engineering, Tufts University, MA 02155, USA
| | - Jeffrey A Herron
- Department of Chemical and Biological Engineering, University of Wisconsin-Madison, WI 53706, USA
| | - Ye Xu
- Department of Chemical Engineering, Louisiana State University, Baton Rouge, LA 70803, USA
| | - Lawrence F Allard
- Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA
| | - Sungsik Lee
- X-ray Science Division, Argonne National Laboratory, 9700 South Cass Avenue, Argonne, IL 60439, USA
| | - Jun Huang
- School of Chemical and Biomolecular Engineering, University of Sydney, NSW 2006, Australia
| | - Manos Mavrikakis
- Department of Chemical and Biological Engineering, University of Wisconsin-Madison, WI 53706, USA
| | | |
Collapse
|