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Fiocco A, Pavlic AA, Kanoufi F, Maisonhaute E, Noël JM, Lucas IT. Electrochemical Tip-Enhanced Raman Spectroscopy for the Elucidation of Complex Electrochemical Reactions. Anal Chem 2024. [PMID: 38340052 DOI: 10.1021/acs.analchem.3c02601] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/12/2024]
Abstract
Tip-enhanced Raman spectroscopy (TERS) is an emerging nanospectroscopy technique whose implementation in situ/operando, namely, in the liquid phase and under electrochemical polarization (EC-TERS), remains challenging. The investigation of electrochemical processes at the nanoscale, in real time and over wide potential windows can be of particular interest but tedious when using EC-STM-TERS. This approach was successfully applied to the investigation of a well-established but yet complex system (a thiolated nitrobenzene derivative 4-NBM) whose reduction mechanism involves various multistep reaction paths, most likely pH-dependent. In light of the EC-TERS analysis carried out under specific conditions limiting the full (6 e-/6 H+) electrochemical reduction of 4-NBM and its photocoupling, a bimolecular electrochemical reaction path, difficult to evidence from the electrochemical response only, is proposed.
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Affiliation(s)
- Alice Fiocco
- Sorbonne Université, CNRS, Laboratoire Interfaces et Systèmes Electrochimiques, LISE, F-75005 Paris, France
- Université Paris Cité, CNRS, ITODYS, F-75013 Paris, France
| | - Aja A Pavlic
- Sorbonne Université, CNRS, Laboratoire Interfaces et Systèmes Electrochimiques, LISE, F-75005 Paris, France
| | | | - Emmanuel Maisonhaute
- Sorbonne Université, CNRS, Laboratoire Interfaces et Systèmes Electrochimiques, LISE, F-75005 Paris, France
| | - Jean-Marc Noël
- Université Paris Cité, CNRS, ITODYS, F-75013 Paris, France
| | - Ivan T Lucas
- Sorbonne Université, CNRS, Laboratoire Interfaces et Systèmes Electrochimiques, LISE, F-75005 Paris, France
- Nantes Université, CNRS, IMN, F-44322 Nantes, France
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Li Z, Xing Y, Liu Y, Meng A, Fan X. Graphene oxide membrane chemically modified by electron-transfer diazonium chemistry for efficient dye separation. RSC Adv 2022; 12:29878-29883. [PMID: 36321079 PMCID: PMC9580474 DOI: 10.1039/d2ra03886b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2022] [Accepted: 10/07/2022] [Indexed: 12/02/2022] Open
Abstract
By chemical modification of the graphene oxide (GO) surface via diazonium chemistry, we introduce nitrobenzene groups as new interlayer pillars to GO memebranes like the surface oxygen-containing functional groups. The larger pillar can finely enlarge the interlayer space of the GO membrane. The filtration performance of modified GO membranes with different mass ratios of nitrobenzene diazonium tetrafluoroborate (NDT) were tested for EB, DR81, and MB. Notably, when the GO : NDT ratio is 1 : 1, it is found that the water flux can be enhanced by more than twice and by nearly 1.4 times its value for EB and DR81, respectively, while maintaining a high rejection (92% for EB and 95% for DR81). In conclusion, the chemical modification of GO through the dediazonization reaction of NDT can indeed improve the separation efficiency of the dye.
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Affiliation(s)
- Zhenjiang Li
- College of Materials Science and Engineering, Qingdao University of Science and TechnologyQingdao 266061ShandongP. R. China
| | - Yucheng Xing
- College of Materials Science and Engineering, Qingdao University of Science and TechnologyQingdao 266061ShandongP. R. China
| | - Yan Liu
- School of Mathematics and Physics, Qingdao University of Science and TechnologyQingdao 266061ShandongP. R. China
| | - Alan Meng
- College of Chemistry and Molecular Engineering, Qingdao University of Science and TechnologyQingdao 266061ShandongP. R. China
| | - Xiaoyan Fan
- School of Mathematics and Physics, Qingdao University of Science and TechnologyQingdao 266061ShandongP. R. China
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3
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Fabrication of devices featuring covalently linked MoS2–graphene heterostructures. Nat Chem 2022; 14:695-700. [DOI: 10.1038/s41557-022-00924-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2021] [Accepted: 03/07/2022] [Indexed: 11/08/2022]
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Li Z, Li K, Wang S, Teng C. Covalent Patterning of Graphene for Controllable Functionalization from Microscale to Nanoscale: A Mini-Review. Front Chem 2022; 10:829614. [PMID: 35360538 PMCID: PMC8963783 DOI: 10.3389/fchem.2022.829614] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2021] [Accepted: 01/31/2022] [Indexed: 11/13/2022] Open
Abstract
Covalent patterning of graphene opens many application possibilities in the field of photonics, electronics, sensors, and catalysis due to order-dependent optical properties, band structure engineering, and processibility and reactivity improvement. Owing to the low reactivity of the graphene basal plane, harsh reagents (e.g., radicals) used for covalent functionalization normally result in poor spatial control, which largely compromises the intrinsic properties of graphene. Therefore, precisely spatial control on covalent patterning of graphene is of great importance. Herein, we summarize recent advances for covalent patterning of graphene from the microscale to nanoscale resolution using different techniques such as laser or electrochemical writing, template-directed growth, and tip-induced nanoshaving.
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Affiliation(s)
- Zhi Li
- Institute of Marine Biomedicine, Shenzhen Polytechnic, Shenzhen, China
- National Laboratory of Solid State Microstructures, College of Engineering and Applied Sciences, Nanjing University, Nanjing, China
- *Correspondence: Zhi Li, ; Chao Teng,
| | - Kai Li
- Institute of Marine Biomedicine, Shenzhen Polytechnic, Shenzhen, China
- National Laboratory of Solid State Microstructures, College of Engineering and Applied Sciences, Nanjing University, Nanjing, China
| | - Shuang Wang
- Institute of Marine Biomedicine, Shenzhen Polytechnic, Shenzhen, China
- National Laboratory of Solid State Microstructures, College of Engineering and Applied Sciences, Nanjing University, Nanjing, China
| | - Chao Teng
- Institute of Marine Biomedicine, Shenzhen Polytechnic, Shenzhen, China
- *Correspondence: Zhi Li, ; Chao Teng,
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Mishyn V, Rodrigues T, Leroux YR, Aspermair P, Happy H, Bintinger J, Kleber C, Boukherroub R, Knoll W, Szunerits S. Controlled covalent functionalization of a graphene-channel of a field effect transistor as an ideal platform for (bio)sensing applications. NANOSCALE HORIZONS 2021; 6:819-829. [PMID: 34569584 DOI: 10.1039/d1nh00355k] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
The controlled covalent functionalization of the graphene channel of a field effect transistor, based on interdigitated gold electrodes (source and drain), via electrochemical grafting, using specifically designed aryl diazonium species is demonstrated to allow the simple fabrication of a general platform for (bio)sensing applications. The electrochemical grafting of a protected ethynylphenyl diazonium salt leads to the deposition of only a monolayer on the graphene channel. This controlled covalent functionalization of the graphene channel results in a charge mobility of the GFET of 1739 ± 376 cm2 V-1 s-1 and 1698 ± 536 cm2 V-1 s-1 for the holes and electrons, respectively, allowing their utilization as (bio)sensors. After deprotection, a dense and compact ethynylphenyl monolayer is obtained and allows the immobilization of a wide range of (bio)molecules by a "click" chemistry coupling reaction (Huisgen 1,3-dipolar cycloaddition). This finding opens promising options for graphene-based (bio)sensing applications.
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Affiliation(s)
- Vladyslav Mishyn
- Univ. Lille, CNRS, Centrale Lille, Univ. Polytechnique Hauts-de-France, UMR 8520 - IEMN, F-59000 Lille, France.
| | - Teresa Rodrigues
- Univ. Lille, CNRS, Centrale Lille, Univ. Polytechnique Hauts-de-France, UMR 8520 - IEMN, F-59000 Lille, France.
- Biosensor Technologies, AIT Austrian Institute of Technology GmbH, 3430 Tulln, Austria.
| | - Yann R Leroux
- Univ. Rennes, CNRS, ISCR - UMR 6226, Campus de Beaulieu, F-35000 Rennes, France.
| | - Patrik Aspermair
- Biosensor Technologies, AIT Austrian Institute of Technology GmbH, 3430 Tulln, Austria.
| | - Henri Happy
- Univ. Lille, CNRS, Centrale Lille, Univ. Polytechnique Hauts-de-France, UMR 8520 - IEMN, F-59000 Lille, France.
| | - Johannes Bintinger
- Biosensor Technologies, AIT Austrian Institute of Technology GmbH, 3430 Tulln, Austria.
| | - Christoph Kleber
- Department of Physics and Chemistry of Materials, Faculty of Medicine/Dental Medicine, Danube Private University, Krems, Austria
| | - Rabah Boukherroub
- Univ. Lille, CNRS, Centrale Lille, Univ. Polytechnique Hauts-de-France, UMR 8520 - IEMN, F-59000 Lille, France.
| | - Wolfgang Knoll
- Biosensor Technologies, AIT Austrian Institute of Technology GmbH, 3430 Tulln, Austria.
- Department of Scientific Coordination and Management, Danube Private University, 3500 Krems, Austria
| | - Sabine Szunerits
- Univ. Lille, CNRS, Centrale Lille, Univ. Polytechnique Hauts-de-France, UMR 8520 - IEMN, F-59000 Lille, France.
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Richard W, Evrard D, Busson B, Humbert C, Dalstein L, Tadjeddine A, Gros P. The reduction of 4-nitrobenzene diazonium electrografted layer: An electrochemical study coupled to in situ sum-frequency generation spectroscopy. Electrochim Acta 2018. [DOI: 10.1016/j.electacta.2018.07.073] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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Pham PV. Cleaning of graphene surfaces by low-pressure air plasma. ROYAL SOCIETY OPEN SCIENCE 2018; 5:172395. [PMID: 29892425 PMCID: PMC5990796 DOI: 10.1098/rsos.172395] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/03/2018] [Accepted: 04/16/2018] [Indexed: 06/08/2023]
Abstract
The polymer residues still present on a chemical vapour-deposited graphene surface after its wet transfer by the poly(methyl methacrylate) method to the arbitrary substrates, tend to cause problems such as electrical degradation and unwanted intentional doping. In this study, by using an effective cleaning method for the graphene surface by air-assisted plasma, the graphene surface was cleaned significantly without damaging the graphene network, which resulted in the reduction (approx. 71.11%) of polymer residues on its surface. The analysis reveals that this approach reduced the D-band (impurities, polymer residues) formation while maintaining the π-bonding of the graphene, which affects conductivity. By characterizations of the optical microscope, Raman spectroscopy and atomic force microscopy, we obtained a significantly cleaner graphene surface (roughness of 4.1 nm) compared to pristine graphene (roughness of 1.2 nm) on a SiO2 substrate. In addition, X-ray photoelectron spectroscopy data revealed that the C1s peak of the air-assisted graphene film was higher than the one of a pristine graphene film, indicating that a cleaner graphene surface was obtained.
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Nouchi R. Contact resistance at planar metal contacts on bilayer graphene and effects of molecular insertion layers. NANOTECHNOLOGY 2017; 28:134003. [PMID: 28167810 DOI: 10.1088/1361-6528/aa5ec2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
The possible origins of metal-bilayer graphene (BLG) contact resistance are investigated by taking into consideration the bandgap formed by interfacial charge transfer at the metal contacts. Our results show that a charge injection barrier (Schottky barrier) does not contribute to the contact resistance because the BLG under the contacts is always degenerately doped. We also showed that the contact-doping-induced increase in the density of states (DOS) of BLG under the metal contacts decreases the contact resistance owing to enhanced charge carrier tunnelling at the contacts. The contact doping can be enhanced by inserting molecular dopant layers into the metal contacts. However, carrier tunnelling through the insertion layer increases the contact resistance, and thus, alternative device structures should be employed. Finally, we showed that the inter-band transport by variable range hopping via in-gap states is the largest contributor to contact resistance when the carrier type of the gated channel is opposite to the contact doping carrier type. This indicates that the strategy of contact resistance reduction by the contact-doping-induced increase in the DOS is effective only for a single channel transport branch (n- or p-type) depending on the contact doping carrier type.
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Affiliation(s)
- Ryo Nouchi
- Nanoscience and Nanotechnology Research Center, Osaka Prefecture University, Sakai, Osaka 599-8570, Japan
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9
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Pham VP, Mishra A, Young Yeom G. The enhancement of Hall mobility and conductivity of CVD graphene through radical doping and vacuum annealing. RSC Adv 2017. [DOI: 10.1039/c7ra01330b] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
We report an innovated method for chlorine doping of graphene utilizing an inductively coupled plasma system.
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Affiliation(s)
- Viet Phuong Pham
- School of Advanced Materials Science and Engineering
- Sungkyunkwan University (SKKU)
- Suwon
- Republic of Korea
- SKKU Advanced Institute of Nano Technology (SAINT)
| | - Anurag Mishra
- School of Advanced Materials Science and Engineering
- Sungkyunkwan University (SKKU)
- Suwon
- Republic of Korea
- Etch Division
| | - Geun Young Yeom
- School of Advanced Materials Science and Engineering
- Sungkyunkwan University (SKKU)
- Suwon
- Republic of Korea
- SKKU Advanced Institute of Nano Technology (SAINT)
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Du P, Bléger D, Charra F, Bouchiat V, Kreher D, Mathevet F, Attias AJ. A versatile strategy towards non-covalent functionalization of graphene by surface-confined supramolecular self-assembly of Janus tectons. BEILSTEIN JOURNAL OF NANOTECHNOLOGY 2015; 6:632-9. [PMID: 25821703 PMCID: PMC4362293 DOI: 10.3762/bjnano.6.64] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/30/2014] [Accepted: 02/10/2015] [Indexed: 06/04/2023]
Abstract
Two-dimensional (2D), supramolecular self-assembly at surfaces is now well-mastered with several existing examples. However, one remaining challenge to enable future applications in nanoscience is to provide potential functionalities to the physisorbed adlayer. This work reviews a recently developed strategy that addresses this key issue by taking advantage of a new concept, Janus tecton materials. This is a versatile, molecular platform based on the design of three-dimensional (3D) building blocks consisting of two faces linked by a cyclophane-type pillar. One face is designed to steer 2D self-assembly onto C(sp(2))-carbon-based flat surfaces, the other allowing for the desired functionality above the substrate with a well-controlled lateral order. In this way, it is possible to simultaneously obtain a regular, non-covalent paving as well as supramolecular functionalization of graphene, thus opening interesting perspectives for nanoscience applications.
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Affiliation(s)
- Ping Du
- Institut Parisien de Chimie Moléculaire, Chimie des Polymères, UMR CNRS 8232, Université Pierre et Marie Curie, 3 rue Galilée, 94200 Ivry, France
| | - David Bléger
- Institut Parisien de Chimie Moléculaire, Chimie des Polymères, UMR CNRS 8232, Université Pierre et Marie Curie, 3 rue Galilée, 94200 Ivry, France
| | - Fabrice Charra
- Laboratoire de Nanophotonique, Service de Physique de l’Etat Condensé CEA/Saclay 91191 Gif sur Yvette Cedex, France
| | - Vincent Bouchiat
- Department Nanosciences Institut Neel, CNRS, Univ. Grenoble-Alpes, 38042 Grenoble Cedex 09, France
| | - David Kreher
- Institut Parisien de Chimie Moléculaire, Chimie des Polymères, UMR CNRS 8232, Université Pierre et Marie Curie, 3 rue Galilée, 94200 Ivry, France
| | - Fabrice Mathevet
- Institut Parisien de Chimie Moléculaire, Chimie des Polymères, UMR CNRS 8232, Université Pierre et Marie Curie, 3 rue Galilée, 94200 Ivry, France
| | - André-Jean Attias
- Institut Parisien de Chimie Moléculaire, Chimie des Polymères, UMR CNRS 8232, Université Pierre et Marie Curie, 3 rue Galilée, 94200 Ivry, France
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Mali KS, Greenwood J, Adisoejoso J, Phillipson R, De Feyter S. Nanostructuring graphene for controlled and reproducible functionalization. NANOSCALE 2015; 7:1566-1585. [PMID: 25553734 DOI: 10.1039/c4nr06470d] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
The 'graphene rush' that started almost a decade ago is far from over. The dazzling properties of graphene have long warranted a number of applications in various domains of science and technology. Harnessing the exceptional properties of graphene for practical applications however has proved to be a massive task. Apart from the challenges associated with the large-scale production of the material, the intrinsic zero band gap, the inherently low reactivity and solubility of pristine graphene preclude its use in several high- as well as low-end applications. One of the potential solutions to these problems is the surface functionalization of graphene using organic building blocks. The 'surface-only' nature of graphene allows the manipulation of its properties not only by covalent chemical modification but also via non-covalent interactions with organic molecules. Significant amount of research efforts have been directed towards the development of functionalization protocols for modifying the structural, electronic, and chemical properties of graphene. This feature article provides a glimpse of recent progress in the molecular functionalization of surface supported graphene using non-covalent as well as covalent chemistry.
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Affiliation(s)
- Kunal S Mali
- KU Leuven-University of Leuven, Department of Chemistry, Division of Molecular Imaging and Photonics Celestijnenlaan 200F, B-3001 Leuven, Belgium.
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Du P, Jaouen M, Bocheux A, Bourgogne C, Han Z, Bouchiat V, Kreher D, Mathevet F, Fiorini-Debuisschert C, Charra F, Attias AJ. Surface-confined self-assembled Janus tectons: a versatile platform towards the noncovalent functionalization of graphene. Angew Chem Int Ed Engl 2014; 53:10060-6. [PMID: 25047257 DOI: 10.1002/anie.201403572] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2014] [Indexed: 11/08/2022]
Abstract
A general strategy for simultaneously generating surface-based supramolecular architectures on flat sp(2) -hybridized carbon supports and independently exposing on demand off-plane functionality with controlled lateral order is highly desirable for the noncovalent functionalization of graphene. Here, we address this issue by providing a versatile molecular platform based on a library of new 3D Janus tectons that form surface-confined supramolecular adlayers in which it is possible to simultaneously steer the 2D self-assembly on flat C(sp(2))-based substrates and tailor the external interface above the substrate by exposure to a wide variety of small terminal chemical groups and functional moieties. This approach is validated throughout by scanning tunneling microscopy (STM) at the liquid-solid interface and molecular mechanics modeling studies. The successful self-assembly on graphene, together with the possibility to transfer the graphene monolayer onto various substrates, should considerably extend the application of our functionalization strategy.
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Affiliation(s)
- Ping Du
- Institut Parisien de Chimie Moléculaire, Chimie des Polymères, UMR CNRS 8232, Université Pierre et Marie Curie, 3 rue Galilée, 94200 Ivry (France)
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Du P, Jaouen M, Bocheux A, Bourgogne C, Han Z, Bouchiat V, Kreher D, Mathevet F, Fiorini-Debuisschert C, Charra F, Attias AJ. Surface-Confined Self-Assembled Janus Tectons: A Versatile Platform towards the Noncovalent Functionalization of Graphene. Angew Chem Int Ed Engl 2014. [DOI: 10.1002/ange.201403572] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Eigler S, Hirsch A. Chemistry with Graphene and Graphene Oxide-Challenges for Synthetic Chemists. Angew Chem Int Ed Engl 2014; 53:7720-38. [DOI: 10.1002/anie.201402780] [Citation(s) in RCA: 635] [Impact Index Per Article: 63.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2014] [Indexed: 11/12/2022]
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Eigler S, Hirsch A. Chemie an Graphen und Graphenoxid - eine Herausforderung für Synthesechemiker. Angew Chem Int Ed Engl 2014. [DOI: 10.1002/ange.201402780] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Shih CJ, Wang QH, Jin Z, Paulus GLC, Blankschtein D, Jarillo-Herrero P, Strano MS. Disorder imposed limits of mono- and bilayer graphene electronic modification using covalent chemistry. NANO LETTERS 2013; 13:809-817. [PMID: 23339830 DOI: 10.1021/nl304632e] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
A central question in graphene chemistry is to what extent chemical modification can control an electronically accessible band gap in monolayer and bilayer graphene (MLG and BLG). Density functional theory predicts gaps in covalently functionalized graphene as high as 2 eV, while this approach neglects the fact that lattice symmetry breaking occurs over only a prescribed radius of nanometer dimension, which we label the S-region. Therefore, high chemical conversion is central to observing this band gap in transport. We use an electrochemical approach involving phenyl-diazonium salts to systematically probe electronic modification in MLG and BLG with increasing functionalization for the first time, obtaining the highest conversion values to date. We find that both MLG and BLG retain their relatively high conductivity after functionalization even at high conversion, as mobility losses are offset by increases in carrier concentration. For MLG, we find that band gap opening as measured during transport is linearly increased with respect to the I(D)/I(G) ratio but remains below 0.1 meV in magnitude for SiO(2) supported graphene. The largest transport band gap obtained in a suspended, highly functionalized (I(D)/I(G) = 4.5) graphene is about 1 meV, lower than our theoretical predictions considering the quantum interference effect between two neighboring S-regions and attributed to its population with midgap states. On the other hand, heavily functionalized BLG (I(D)/I(G) = 1.8) still retains its signature dual-gated band gap opening due to electric-field symmetry breaking. We find a notable asymmetric deflection of the charge neutrality point (CNP) under positive bias which increases the apparent on/off current ratio by 50%, suggesting that synergy between symmetry breaking, disorder, and quantum interference may allow the observation of new transistor phenomena. These important observations set definitive limits on the extent to which chemical modification can control graphene electronically.
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Affiliation(s)
- Chih-Jen Shih
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
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Paulus GLC, Wang QH, Strano MS. Covalent electron transfer chemistry of graphene with diazonium salts. Acc Chem Res 2013; 46:160-70. [PMID: 22946516 DOI: 10.1021/ar300119z] [Citation(s) in RCA: 169] [Impact Index Per Article: 15.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Graphene is an atomically thin, two-dimensional allotrope of carbon with exceptionally high carrier mobilities, thermal conductivity, and mechanical strength. From a chemist's perspective, graphene can be regarded as a large polycyclic aromatic molecule and as a surface without a bulk contribution. Consequently, chemistries typically performed on organic molecules and surfaces have been used as starting points for the chemical functionalization of graphene. The motivations for chemical modification of graphene include changing its doping level, opening an electronic band gap, charge storage, chemical and biological sensing, making new composite materials, and the scale-up of solution-processable graphene. In this Account, we focus on graphene functionalization via electron transfer chemistries, in particular via reactions with aryl diazonium salts. Because electron transfer chemistries depend on the Fermi energy of graphene and the density of states of the reagents, the resulting reaction rate depends on the number of graphene layers, edge states, defects, atomic structure, and the electrostatic environment. We limit our Account to focus on pristine graphene over graphene oxide, because free electrons in the latter are already bound to oxygen-containing functionalities and the resulting chemistries are dominated by localized reactivity and defects. We describe the reaction mechanism of diazonium functionalization of graphene and show that the reaction conditions determine the relative degrees of chemisorption and physisorption, which allows for controlled modulation of the electronic properties of graphene. Finally we discuss different applications for graphene modified by this chemistry, including as an additive in polymer matrices, as biosensors when coupled with cells and biomolecules, and as catalysts when combined with nanoparticles.
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Affiliation(s)
- Geraldine L. C. Paulus
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Qing Hua Wang
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Michael S. Strano
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
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Wu Q, Wu Y, Hao Y, Geng J, Charlton M, Chen S, Ren Y, Ji H, Li H, Boukhvalov DW, Piner RD, Bielawski CW, Ruoff RS. Selective surface functionalization at regions of high local curvature in graphene. Chem Commun (Camb) 2013; 49:677-9. [DOI: 10.1039/c2cc36747e] [Citation(s) in RCA: 119] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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Understanding and controlling the substrate effect on graphene electron-transfer chemistry via reactivity imprint lithography. Nat Chem 2012; 4:724-32. [DOI: 10.1038/nchem.1421] [Citation(s) in RCA: 416] [Impact Index Per Article: 34.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2012] [Accepted: 06/27/2012] [Indexed: 12/24/2022]
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