1
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Neumann S, Doebler HH, Keil S, Erdt AJ, Gutsche C, Borchert H, Kolny-Olesiak J, Parisi J, Bäumer M, Kunz S. Effects of Particle Size on Strong Metal–Support Interactions Using Colloidal “Surfactant-Free” Pt Nanoparticles Supported on Fe 3O 4. ACS Catal 2020. [DOI: 10.1021/acscatal.9b04367] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Sarah Neumann
- Institute of Applied and Physical Chemistry (IAPC), Center for Environmental Research and Sustainable Technology, University of Bremen, Leobener Strasse 6, 28359 Bremen, Germany
- MAPEX Center for Materials and Processes, University of Bremen, Bibliothekstrasse 1, 28350 Bremen, Germany
| | - Hans Hannes Doebler
- Institute of Applied and Physical Chemistry (IAPC), Center for Environmental Research and Sustainable Technology, University of Bremen, Leobener Strasse 6, 28359 Bremen, Germany
- MAPEX Center for Materials and Processes, University of Bremen, Bibliothekstrasse 1, 28350 Bremen, Germany
| | - Simona Keil
- Institute of Applied and Physical Chemistry (IAPC), Center for Environmental Research and Sustainable Technology, University of Bremen, Leobener Strasse 6, 28359 Bremen, Germany
- MAPEX Center for Materials and Processes, University of Bremen, Bibliothekstrasse 1, 28350 Bremen, Germany
| | - Alexandra J. Erdt
- Energy and Semiconductor Research Laboratory, Department of Physics, Carl von Ossietzky University of Oldenburg, 26111 Oldenburg, Germany
| | - Christian Gutsche
- Energy and Semiconductor Research Laboratory, Department of Physics, Carl von Ossietzky University of Oldenburg, 26111 Oldenburg, Germany
| | - Holger Borchert
- Energy and Semiconductor Research Laboratory, Department of Physics, Carl von Ossietzky University of Oldenburg, 26111 Oldenburg, Germany
| | - Joanna Kolny-Olesiak
- Energy and Semiconductor Research Laboratory, Department of Physics, Carl von Ossietzky University of Oldenburg, 26111 Oldenburg, Germany
| | - Jürgen Parisi
- Energy and Semiconductor Research Laboratory, Department of Physics, Carl von Ossietzky University of Oldenburg, 26111 Oldenburg, Germany
| | - Marcus Bäumer
- Institute of Applied and Physical Chemistry (IAPC), Center for Environmental Research and Sustainable Technology, University of Bremen, Leobener Strasse 6, 28359 Bremen, Germany
- MAPEX Center for Materials and Processes, University of Bremen, Bibliothekstrasse 1, 28350 Bremen, Germany
| | - Sebastian Kunz
- Institute of Applied and Physical Chemistry (IAPC), Center for Environmental Research and Sustainable Technology, University of Bremen, Leobener Strasse 6, 28359 Bremen, Germany
- MAPEX Center for Materials and Processes, University of Bremen, Bibliothekstrasse 1, 28350 Bremen, Germany
- Südzucker AG, Central Department Research, Development, and Services (CRDS), Wormser Strasse 11, 67283 Obrigheim, Germany
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2
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Erdt AJ, Gutsche C, Fittschen UEA, Borchert H, Parisi J, Kolny-Olesiak J. Control of crystallographic phases and surface characterization of intermetallic platinum tin nanoparticles. CrystEngComm 2019. [DOI: 10.1039/c9ce00356h] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Colloidal synthesis and characterization of intermetallic tin-rich platinum–tin nanoparticles with detailed surface characterization.
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Affiliation(s)
- Alexandra J. Erdt
- Energy and Semiconductor Research Laboratory
- Department of Physics
- Carl von Ossietzky University of Oldenburg
- D-26111 Oldenburg
- Germany
| | - Christian Gutsche
- Energy and Semiconductor Research Laboratory
- Department of Physics
- Carl von Ossietzky University of Oldenburg
- D-26111 Oldenburg
- Germany
| | - Ursula E. A. Fittschen
- Material Analysis and Functional Solid Matter Group
- Institute of Inorganic and Analytical Chemistry
- TU Clausthal
- D-38678 Clausthal-Zellerfeld
- Germany
| | - Holger Borchert
- Energy and Semiconductor Research Laboratory
- Department of Physics
- Carl von Ossietzky University of Oldenburg
- D-26111 Oldenburg
- Germany
| | - Jürgen Parisi
- Energy and Semiconductor Research Laboratory
- Department of Physics
- Carl von Ossietzky University of Oldenburg
- D-26111 Oldenburg
- Germany
| | - Joanna Kolny-Olesiak
- Energy and Semiconductor Research Laboratory
- Department of Physics
- Carl von Ossietzky University of Oldenburg
- D-26111 Oldenburg
- Germany
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3
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Tchamba Yimga N, Ramanan C, Borchert H, Parisi J, Untenecker H, Kirsch P, von Hauff E. Interplay between Long-Range Crystal Order and Short-Range Molecular Interactions Tunes Carrier Mobility in Liquid Crystal Dyes. ACS Appl Mater Interfaces 2017; 9:6228-6236. [PMID: 28139915 PMCID: PMC5330658 DOI: 10.1021/acsami.6b14715] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/17/2016] [Accepted: 01/31/2017] [Indexed: 06/06/2023]
Abstract
We investigated the influence of molecular packing on the optical and electrical properties of the liquid crystalline dye 4,7-bis[5-(2-fluoro-4-pentyl-phenyl)-2-thienyl]-2,1,3-benzothiadiazole (FPPTB). FPPTB is crystalline at room temperature, exhibits a nematic phase at temperatures above 149 °C and is in an isotropic melt at temperatures above 230 °C. Solution processed FPPTB films were subject to thermal annealing through these phase transition temperatures and characterized with X-ray diffraction and polarized optical microscopy. Cooling FPPTB films from the nematic and isotropic phases increased crystal domain size, but also induced local structural variations in the molecular packing of crystalline FPPTB. The decrease in long-range order was correlated with an increase in short-range π-π interactions, leading to changes in molecular aggregation which persisted even when the FPPTB films were cooled to room temperature. Annealing-induced changes in molecular aggregation were confirmed with optical spectroscopy. The carrier mobility in FPPTB films increased over 2 orders of magnitude from (2.2 ± 0.4) × 10-5 cm2 V-1 s-1 in as-spun films to μ = (5.0 ± 0.8) × 10-3 cm2 V-1 s-1 in films cooled from the isotropic melt. We discuss the relationship between thermal stability and high carrier mobility values in terms of the interplay between long-range molecular order and increased π-π interactions between molecular pairs in the FPPTB film.
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Affiliation(s)
- Nadine Tchamba Yimga
- Physics
of Energy, Department of Physics and Astronomy, Vrije Universiteit Amsterdam, De Boelelaan 1081, 1081 HV Amsterdam, The Netherlands
- Energy
and Semiconductor Research Laboratory, Institute of Physics, Carl von Ossietzky University of Oldenburg, Carl-von-Ossietzky-Strasse 9-11, 26129 Oldenburg, Germany
| | - Charusheela Ramanan
- Physics
of Energy, Department of Physics and Astronomy, Vrije Universiteit Amsterdam, De Boelelaan 1081, 1081 HV Amsterdam, The Netherlands
| | - Holger Borchert
- Energy
and Semiconductor Research Laboratory, Institute of Physics, Carl von Ossietzky University of Oldenburg, Carl-von-Ossietzky-Strasse 9-11, 26129 Oldenburg, Germany
| | - Jürgen Parisi
- Energy
and Semiconductor Research Laboratory, Institute of Physics, Carl von Ossietzky University of Oldenburg, Carl-von-Ossietzky-Strasse 9-11, 26129 Oldenburg, Germany
| | - Harald Untenecker
- Liquid
Crystals R&D Chemistry, Merck KGaA, Frankfurter Strasse 250, 64293 Darmstadt, Germany
| | - Peer Kirsch
- Liquid
Crystals R&D Chemistry, Merck KGaA, Frankfurter Strasse 250, 64293 Darmstadt, Germany
| | - Elizabeth von Hauff
- Physics
of Energy, Department of Physics and Astronomy, Vrije Universiteit Amsterdam, De Boelelaan 1081, 1081 HV Amsterdam, The Netherlands
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4
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Abstract
Heterojunction solar cells based on colloidal nanocrystals (NCs) have shown remarkable improvements in performance in the last decade, but this progress is limited to merely two materials, PbS and PbSe. However, solar cells based on other material systems such as copper-based compounds show lower power conversion efficiencies and much less effort has been made to develop a better understanding of factors limiting their performance. Here, we study charge carrier loss mechanisms in solution-processed CuInS2/ZnO NC solar cells by combining steady-state measurements with transient photocurrent and photovoltage measurements. We demonstrate the presence of an extraction barrier at the CuInS2/ZnO interface, which can be reduced upon illumination with UV light. However, trap-assisted recombination in the CuInS2 layer is shown to be the dominant decay process in these devices.
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Affiliation(s)
- Dorothea Scheunemann
- Energy and Semiconductor Research Laboratory, Department of Physics, University of Oldenburg, Carl-von-Ossietzky-Straße 9-11, 26129 Oldenburg, Germany.
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5
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Gutsche C, Moeller CJ, Knipper M, Borchert H, Parisi J, Plaggenborg T. Influence of Vanadium Ions on the Degradation Behavior of Platinum Catalysts for Oxygen Reduction Reaction. Electrocatalysis (N Y) 2015. [DOI: 10.1007/s12678-015-0264-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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6
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Eck M, Pham CV, Züfle S, Neukom M, Sessler M, Scheunemann D, Erdem E, Weber S, Borchert H, Ruhstaller B, Krüger M. Improved efficiency of bulk heterojunction hybrid solar cells by utilizing CdSe quantum dot-graphene nanocomposites. Phys Chem Chem Phys 2015; 16:12251-60. [PMID: 24820059 DOI: 10.1039/c4cp01566e] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We present a significant efficiency enhancement of hybrid bulk heterojunction solar cells by utilizing CdSe quantum dots attached to reduced graphene oxide (rGO) as the electron accepting phase, blended with the PCPDTBT polymer. The quantum dot attachment to rGO was achieved following a self-assembly approach, recently developed, using thiolated reduced graphene oxide (TrGO) to form a TrGO-CdSe nanocomposite. Therefore, we are able to obtain TrGO-CdSe quantum dot/PCPDTBT bulk-heterojunction hybrid solar cells with power conversion efficiencies of up to 4.2%, compared with up to 3% for CdSe quantum dot/PCPDTBT devices. The improvement is mainly due to an increase of the open-circuit voltage from 0.55 V to 0.72 V. We found evidence for a significant change in the heterojunction donor-acceptor blend nanomorphology, observable by a more vertical alignment of the TrGO-quantum dot nanocomposites in the z-direction and a different nanophase separation in the x-y direction compared to the quantum dot only containing device. Moreover, an improved charge extraction and trap state reduction were observed for TrGO containing hybrid solar cells.
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Affiliation(s)
- Michael Eck
- Freiburg Materials Research Center (FMF), University of Freiburg, Stefan-Meier-Straße 21, D-79104 Freiburg, Germany.
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7
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Wilken S, Wilkens V, Scheunemann D, Nowak RE, von Maydell K, Parisi J, Borchert H. Semitransparent polymer-based solar cells with aluminum-doped zinc oxide electrodes. ACS Appl Mater Interfaces 2015; 7:287-300. [PMID: 25495167 DOI: 10.1021/am5061917] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
With the use of two transparent electrodes, organic polymer-fullerene solar cells are semitransparent and may be combined to parallel-connected multijunction devices or used for innovative applications like power-generating windows. A challenging issue is the optimization of the electrodes, to combine high transparency with adequate electric properties. In the present work, we study the potential of sputter-deposited aluminum-doped zinc oxide as an alternative to the widely used but relatively expensive indium tin oxide (ITO) as cathode material in semitransparent polymer-fullerene solar cells. Concerning the anode, we utilized an insulator-metal-insulator structure based on ultrathin Au films embedded between two evaporated MoO3 layers, with the outer MoO3 film (capping layer) serving as a light coupling layer. The performance of the ITO-free semitransparent polymer-fullerene solar cells was systematically studied as dependent on the thickness of the capping layer and the active layer as well as the illumination direction. These variations were found to have strong impact on the obtained photocurrent densities. We performed optical simulations of the electric field distribution within the devices using the transfer-matrix method, to analyze the origin of the current density variations in detail and provide deep insight into the device physics. With the conventional absorber materials studied here, optimized ITO-free and semitransparent devices reached 2.0% power conversion efficiency and a maximum optical transmission of 60%, with the device concept being potentially transferable to other absorber materials.
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Affiliation(s)
- Sebastian Wilken
- Energy and Semiconductor Research Laboratory, Department of Physics, Carl von Ossietzky University of Oldenburg , Carl-von-Ossietzky-Strasse 9-11, 26129 Oldenburg, Germany
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8
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Altmann L, Wang X, Borchert H, Kolny-Olesiak J, Zielasek V, Parisi J, Kunz S, Bäumer M. Influence of Sn content on the hydrogenation of crotonaldehyde catalysed by colloidally prepared PtSn nanoparticles. Phys Chem Chem Phys 2015; 17:28186-92. [DOI: 10.1039/c5cp00280j] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
For increasing tin concentrations PtSn nanoparticles of similar size show a monotonically increasing selectivity towards crotylalcohol and a volcano like activity.
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Affiliation(s)
- Lena Altmann
- Institute of Applied and Physical Chemistry and Center for Environmental Research and Sustainable Technology
- University of Bremen Leobener Str. UFT
- D-28359 Bremen
- Germany
| | - Xiaodong Wang
- Technical Electrochemistry
- Faculty of Chemistry Technische Universität München
- D-85748 Garching
- Germany
| | - Holger Borchert
- Energy and Semiconductor Research Laboratory
- Department of Physics
- University of Oldenburg
- D-26129 Oldenburg
- Germany
| | - Joanna Kolny-Olesiak
- Energy and Semiconductor Research Laboratory
- Department of Physics
- University of Oldenburg
- D-26129 Oldenburg
- Germany
| | - Volkmar Zielasek
- Institute of Applied and Physical Chemistry and Center for Environmental Research and Sustainable Technology
- University of Bremen Leobener Str. UFT
- D-28359 Bremen
- Germany
| | - Jürgen Parisi
- Energy and Semiconductor Research Laboratory
- Department of Physics
- University of Oldenburg
- D-26129 Oldenburg
- Germany
| | - Sebastian Kunz
- Institute of Applied and Physical Chemistry and Center for Environmental Research and Sustainable Technology
- University of Bremen Leobener Str. UFT
- D-28359 Bremen
- Germany
| | - Marcus Bäumer
- Institute of Applied and Physical Chemistry and Center for Environmental Research and Sustainable Technology
- University of Bremen Leobener Str. UFT
- D-28359 Bremen
- Germany
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9
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Abstract
Abstract
Colloidal semiconductor nanocrystals with tunable optical properties
are promising materials for light harvesting in solar cells. So far,
in particular cadmium and lead chalcogenide nanocrystals were
intensively studied in this respect, and the device performance has
made rapid progress in recent years. In contrast, less research
efforts were undertaken to develop solar cells based on Cd- and
Pb-free nanoparticles as absorber material. In the present work, we
report on Schottky solar cells with the absorber layer made of
colloidal copper indium disulfide nanocrystals. Absorber films with up
to ∼ 500 nm thickness were realized by a solution-based
layer-by-layer deposition technique. The device performance was
systematically studied dependent on the absorber layer
thickness. Decreasing photocurrent densities with increasing thickness
revealed charge transport to be a limiting factor for the device
performance.
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Affiliation(s)
- Holger Borchert
- Carl von Ossietzky University of Oldenburg, Department of Physics, Energy and Semiconductor Research Laboratory, Carl-von-Ossietzky-Str. 9–11, 26129 Oldenburg, Germany
| | - Dorothea Scheunemann
- Carl von Ossietzky University of Oldenburg, Department of Physics, Energy and Semiconductor Research Laboratory, Carl-von-Ossietzky-Str. 9–11, 26129 Oldenburg, Germany
| | - Katja Frevert
- Carl von Ossietzky University of Oldenburg, Department of Physics, Energy and Semiconductor Research Laboratory, Carl-von-Ossietzky-Str. 9–11, 26129 Oldenburg, Germany
| | - Florian Witt
- Carl von Ossietzky University of Oldenburg, Department of Physics, Energy and Semiconductor Research Laboratory, Carl-von-Ossietzky-Str. 9–11, 26129 Oldenburg, Germany
| | - Andreas Klein
- Technische Universität Darmstadt, Department of Materials and Geosciences, Surface Science Division, Jovanka-Bontschits-Straße 2, 64287 Darmstadt, Germany
| | - Jürgen Parisi
- Carl von Ossietzky University of Oldenburg, Department of Physics, Energy and Semiconductor Research Laboratory, Carl-von-Ossietzky-Str. 9–11, 26129 Oldenburg, Germany
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10
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Brück S, Krause C, Turrisi R, Beverina L, Wilken S, Saak W, Lützen A, Borchert H, Schiek M, Parisi J. Structure-property relationship of anilino-squaraines in organic solar cells. Phys Chem Chem Phys 2013; 16:1067-77. [PMID: 24288034 DOI: 10.1039/c3cp54163k] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Soluble molecular semiconductors are a promising alternative to semiconducting polymers in the field of organic photovoltaics. Here, three custom-made symmetric 1,3-bis(N,N-alkylated-2,6-dihydroxy-anilino)squaraines containing systematic variations in their molecular structures are compared regarding their applicability as donor materials in bulk-heterojunction solar cells. The terminal substitution pattern of the squaraines is varied from cyclic over linear to branched including a stereogenic center. Single crystal structures are determined, and, in the case of chiral squaraine, unusual formation of stereoisomer co-crystals is revealed. The thin film absorbance spectra show characteristic signatures of H- and J-bands or hint at the formation of tautomers. The general feasibility of these model compounds for photovoltaic applications is studied by light-induced electron spin resonance spectroscopy. The impact of the different molecular substitution patterns on aggregation behavior and, consequently, their optoelectronic solid state properties including charge carrier mobility and finally the solar cell performance are investigated.
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Affiliation(s)
- S Brück
- Institute of Physics, Energy and Semiconductor Research Laboratory, Carl von Ossietzky University of Oldenburg, D-26111 Oldenburg, Germany.
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11
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Altmann L, Wang X, Stöver J, Klink M, Zielasek V, Thiel K, Kolny-Olesiak J, Al-Shamery K, Borchert H, Parisi J, Bäumer M. Impact of Organic Ligands on the Structure and Hydrogenation Performance of Colloidally Prepared Bimetallic PtSn Nanoparticles. ChemCatChem 2013. [DOI: 10.1002/cctc.201200849] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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12
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Kruszynska M, Borchert H, Bachmatiuk A, Rümmeli MH, Büchner B, Parisi J, Kolny-Olesiak J. Size and shape control of colloidal copper(I) sulfide nanorods. ACS Nano 2012; 6:5889-96. [PMID: 22712468 DOI: 10.1021/nn302448n] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
Many physical and chemical properties of semiconducting nanocrystals strongly depend on their spatial dimensions and crystallographic structure. For these reasons, achieving a high degree of size and shape control plays an important role with respect to their application potential. In this report we present a facile route for the direct colloidal synthesis of copper(I) sulfide nanorods. A high reactivity of the starting materials is essential to obtain nanorods. We achieve this by using a thiol that thermally decomposes easily and serves as the sulfur source. The thiol is mixed in a noncoordinating solvent, which acts as the reaction medium. Adjustment of the nucleation temperature makes it possible to tailor uniform nanorods with lengths from 10 to 100 nm. The nanorods are single crystalline, and the growth direction is shown to occur along the a-axis of djurleite. The growth process and character of the nanorods were investigated through UV-vis and NIR absorption spectroscopy, transmission electron microscopy, and powder X-ray diffraction measurements.
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Affiliation(s)
- Marta Kruszynska
- Department of Physics, Energy and Semiconductor Research Laboratory, University of Oldenburg, Carl-von-Ossietzky-Straße 9-11, 26129 Oldenburg, Germany
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13
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Witt E, Witt F, Trautwein N, Fenske D, Neumann J, Borchert H, Parisi J, Kolny-Olesiak J. Synthesis of lead chalcogenide nanocrystals and study of charge transfer in blends of PbSe nanocrystals and poly(3-hexylthiophene). Phys Chem Chem Phys 2012; 14:11706-14. [DOI: 10.1039/c2cp41584d] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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14
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Wang X, Stöver J, Zielasek V, Altmann L, Thiel K, Al-Shamery K, Bäumer M, Borchert H, Parisi J, Kolny-Olesiak J. Colloidal synthesis and structural control of PtSn bimetallic nanoparticles. Langmuir 2011; 27:11052-11061. [PMID: 21761930 DOI: 10.1021/la201829y] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
PtSn bimetallic nanoparticles with different particle sizes (1-9 nm), metal compositions (Sn content of 10-80 mol %), and organic capping agents (e.g., amine, thiol, carboxylic acid and polymer) were synthesized by colloidal chemistry methods. Transmission electron microscopy (TEM) measurements show that, depending on the particle size, the as-prepared bimetallic nanocrystals have quasi-spherical or faceted shapes. Energy-dispersive X-ray (EDX) analyses indicate that for all samples the signals of both Pt and Sn can be detected from single nanoparticles, confirming that the products are actually bimetallic but not only a physical mixture of pure Pt and Sn metal nanoparticles. X-ray diffraction (XRD) measurements were also conducted on the bimetallic particle systems. When compared with the diffraction patterns of monometallic Pt nanoparticles, the bimetallic samples show distinct shifts of the Bragg reflections to lower degrees, which gives clear proof of the alloying of Pt with Sn. However, a quantitative analysis of the lattice parameter shifts indicates that only part of the Sn atoms are incorporated into the alloy nanocrystals. This is consistent with X-ray photoelectron spectroscopy (XPS) measurements that reveal the segregation of Sn at the surfaces of the nanocrystals. Moreover, short PtSn bimetallic nanowires were synthesized by a seed-mediated growth method with amine-capped bimetallic particles as precursors. The resulting nanowires have an average width of 2.3 nm and lengths ranging from 5 to 20 nm.
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Affiliation(s)
- Xiaodong Wang
- EHF Laboratory, Department of Physics, University of Oldenburg, Carl-von-Ossietzky-Strasse 9-11, 26129 Oldenburg, Germany.
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15
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Wang X, Sonström P, Arndt D, Stöver J, Zielasek V, Borchert H, Thiel K, Al-Shamery K, Bäumer M. Heterogeneous catalysis with supported platinum colloids: A systematic study of the interplay between support and functional ligands. J Catal 2011. [DOI: 10.1016/j.jcat.2010.11.020] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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16
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Affiliation(s)
- Marta Kruszynska
- University of Oldenburg, Department of Physics, Energy and Semiconductor Research Laboratory, Carl-von-Ossietzky-Str. 9-11, 26129 Oldenburg, Germany
| | - Holger Borchert
- University of Oldenburg, Department of Physics, Energy and Semiconductor Research Laboratory, Carl-von-Ossietzky-Str. 9-11, 26129 Oldenburg, Germany
| | - Jürgen Parisi
- University of Oldenburg, Department of Physics, Energy and Semiconductor Research Laboratory, Carl-von-Ossietzky-Str. 9-11, 26129 Oldenburg, Germany
| | - Joanna Kolny-Olesiak
- University of Oldenburg, Department of Physics, Energy and Semiconductor Research Laboratory, Carl-von-Ossietzky-Str. 9-11, 26129 Oldenburg, Germany
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17
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Krylova G, Dimitrijevic NM, Talapin DV, Guest JR, Borchert H, Lobo A, Rajh T, Shevchenko EV. Probing the Surface of Transition-Metal Nanocrystals by Chemiluminesence. J Am Chem Soc 2010; 132:9102-10. [DOI: 10.1021/ja102413k] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Galyna Krylova
- Center for Nanoscale Materials, Argonne National Laboratory, Argonne, Illinois 60439, Chemical Sciences and Engineering Division, Argonne National Laboratory, Argonne, Illinois 60439, Department of Chemistry, University of Chicago, Chicago, Illinois 60637, Energy and Semiconductor Research laboratory, Department of Physics, University of Oldenburg, Oldenburg, 26111, Germany, and HASYLAB at DESY, Hamburg, D-22607, Germany
| | - Nada M. Dimitrijevic
- Center for Nanoscale Materials, Argonne National Laboratory, Argonne, Illinois 60439, Chemical Sciences and Engineering Division, Argonne National Laboratory, Argonne, Illinois 60439, Department of Chemistry, University of Chicago, Chicago, Illinois 60637, Energy and Semiconductor Research laboratory, Department of Physics, University of Oldenburg, Oldenburg, 26111, Germany, and HASYLAB at DESY, Hamburg, D-22607, Germany
| | - Dmitri V. Talapin
- Center for Nanoscale Materials, Argonne National Laboratory, Argonne, Illinois 60439, Chemical Sciences and Engineering Division, Argonne National Laboratory, Argonne, Illinois 60439, Department of Chemistry, University of Chicago, Chicago, Illinois 60637, Energy and Semiconductor Research laboratory, Department of Physics, University of Oldenburg, Oldenburg, 26111, Germany, and HASYLAB at DESY, Hamburg, D-22607, Germany
| | - Jeffrey R. Guest
- Center for Nanoscale Materials, Argonne National Laboratory, Argonne, Illinois 60439, Chemical Sciences and Engineering Division, Argonne National Laboratory, Argonne, Illinois 60439, Department of Chemistry, University of Chicago, Chicago, Illinois 60637, Energy and Semiconductor Research laboratory, Department of Physics, University of Oldenburg, Oldenburg, 26111, Germany, and HASYLAB at DESY, Hamburg, D-22607, Germany
| | - Holger Borchert
- Center for Nanoscale Materials, Argonne National Laboratory, Argonne, Illinois 60439, Chemical Sciences and Engineering Division, Argonne National Laboratory, Argonne, Illinois 60439, Department of Chemistry, University of Chicago, Chicago, Illinois 60637, Energy and Semiconductor Research laboratory, Department of Physics, University of Oldenburg, Oldenburg, 26111, Germany, and HASYLAB at DESY, Hamburg, D-22607, Germany
| | - Arun Lobo
- Center for Nanoscale Materials, Argonne National Laboratory, Argonne, Illinois 60439, Chemical Sciences and Engineering Division, Argonne National Laboratory, Argonne, Illinois 60439, Department of Chemistry, University of Chicago, Chicago, Illinois 60637, Energy and Semiconductor Research laboratory, Department of Physics, University of Oldenburg, Oldenburg, 26111, Germany, and HASYLAB at DESY, Hamburg, D-22607, Germany
| | - Tijana Rajh
- Center for Nanoscale Materials, Argonne National Laboratory, Argonne, Illinois 60439, Chemical Sciences and Engineering Division, Argonne National Laboratory, Argonne, Illinois 60439, Department of Chemistry, University of Chicago, Chicago, Illinois 60637, Energy and Semiconductor Research laboratory, Department of Physics, University of Oldenburg, Oldenburg, 26111, Germany, and HASYLAB at DESY, Hamburg, D-22607, Germany
| | - Elena V. Shevchenko
- Center for Nanoscale Materials, Argonne National Laboratory, Argonne, Illinois 60439, Chemical Sciences and Engineering Division, Argonne National Laboratory, Argonne, Illinois 60439, Department of Chemistry, University of Chicago, Chicago, Illinois 60637, Energy and Semiconductor Research laboratory, Department of Physics, University of Oldenburg, Oldenburg, 26111, Germany, and HASYLAB at DESY, Hamburg, D-22607, Germany
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Topp K, Borchert H, Johnen F, Tunc AV, Knipper M, von Hauff E, Parisi J, Al-Shamery K. Impact of the incorporation of Au nanoparticles into polymer/fullerene solar cells. J Phys Chem A 2010; 114:3981-9. [PMID: 20030383 DOI: 10.1021/jp910227x] [Citation(s) in RCA: 125] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The addition of small amounts of dodecylamine-capped Au nanoparticles into the active layer of organic bulk heterojunction solar cells consisting of poly(3-octylthiophene) (P3OT) and C(60) was recently suggested to have a positive impact on device performance due to improved electron transport. This issue was systematically further investigated in the present work. Different strategies to incorporate colloidally prepared Au nanoparticles with a narrow size distribution into organic solar cells with the more common donor/acceptor system consisting of poly(3-hexylthiophene) (P3HT) and [6,6]-phenyl C(61)-butyric acid methyl ester (PCBM) were pursued. Au nanoparticles were prepared with either P3HT or dodecylamine as ligands. Additionally, efforts were undertaken to incorporate nearly ligand-free Au nanoparticles into the system. Therefore, a procedure was successfully developed to remove the dodecylamine ligand shell by a postpreparative ligand exchange with pyridine, a much smaller molecule that can later partly be removed from solid films by annealing. However, for all types of nanoparticles studied here, the performance of the P3HT/PCBM solar cells was found to decrease with the Au particles as an additive to the active layer, meaning that adding Au nanoparticles is not a suitable strategy in the case of the P3HT/PCBM system. Possible reasons are discussed on the basis of detailed investigations of the structure, photophysics and charge transport in the system.
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Affiliation(s)
- K Topp
- Institute of Pure and Applied Chemistry, University of Oldenburg, Carl-von-Ossietzky-Strasse 9-11, 26129 Oldenburg, Germany
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Fenske D, Sonström P, Stöver J, Wang X, Borchert H, Parisi J, Kolny-Olesiak J, Bäumer M, Al-Shamery K. Colloidally Prepared Pt Nanoparticles for Heterogeneous Gas-Phase Catalysis: Influence of Ligand Shell and Catalyst Loading on CO Oxidation Activity. ChemCatChem 2010. [DOI: 10.1002/cctc.200900232] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Jürgens B, Borchert H, Ahrenstorf K, Sonström P, Pretorius A, Schowalter M, Gries K, Zielasek V, Rosenauer A, Weller H, Bäumer M. Kolloidchemisch präparierte Nanopartikel zur Herstellung wohldefinierter und hochaktiver Heterogenkatalysatoren. Angew Chem Int Ed Engl 2008. [DOI: 10.1002/ange.200802188] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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21
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Jürgens B, Borchert H, Ahrenstorf K, Sonström P, Pretorius A, Schowalter M, Gries K, Zielasek V, Rosenauer A, Weller H, Bäumer M. Colloidally Prepared Nanoparticles for the Synthesis of Structurally Well-Defined and Highly Active Heterogeneous Catalysts. Angew Chem Int Ed Engl 2008; 47:8946-9. [DOI: 10.1002/anie.200802188] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Fenske D, Borchert H, Kehres J, Kröger R, Parisi J, Kolny-Olesiak J. Colloidal synthesis of pt nanoparticles: on the formation and stability of nanowires. Langmuir 2008; 24:9011-9016. [PMID: 18646780 DOI: 10.1021/la800259y] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Catalytic properties of Pt nanoparticles can significantly depend on the crystallite shape, which renders shape control an important aim in the chemical synthesis. Starting from a colloidal synthesis of quasispherical Pt nanocrystals capped with dodecylamine ligands, systematic variations of different synthesis parameters were performed in the present work in order to obtain Pt nanowires. Mechanistic investigations revealed that nanowires can form by aggregation of quasispherical particles. The process of wire formation was found to be influenced by parameters such as the concentration of the stabilizing ligands on the particle surface. Furthermore, the thermal stability of the obtained nanoparticles was examined. The nanowires were found to be stable up to approximately 140-160 degrees C. In this temperature range a structural transition to a more spherical crystallite shape occurred, which can be understood by thermodynamic considerations.
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Affiliation(s)
- D Fenske
- Institute of Pure and Applied Chemistry and Center of Interface Science, University of Oldenburg, Carl-von-Ossietzky-Str. 9-11, Oldenburg, Germany
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Nowitzki T, Borchert H, Jürgens B, Risse T, Zielasek V, Bäumer M. UHV Studies of Methanol Decomposition on Mono- and Bimetallic CoPd Nanoparticles Supported on Thin Alumina Films. Chemphyschem 2008; 9:729-39. [DOI: 10.1002/cphc.200700663] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Borchert H, Fenske D, Kolny-Olesiak J, Parisi J, Al-Shamery K, Bäumer M. Ligandenstabilisierte Pt-Nanokristalle als Katalysatoren auf einem Oxidträger: FT-IR-spektroskopische Untersuchungen zur Adsorption und Oxidation von CO. Angew Chem Int Ed Engl 2007. [DOI: 10.1002/ange.200604460] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Borchert H, Fenske D, Kolny-Olesiak J, Parisi J, Al-Shamery K, Bäumer M. Ligand-Capped Pt Nanocrystals as Oxide-Supported Catalysts: FTIR Spectroscopic Investigations of the Adsorption and Oxidation of CO. Angew Chem Int Ed Engl 2007; 46:2923-6. [PMID: 17357165 DOI: 10.1002/anie.200604460] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Holger Borchert
- Institute of Applied and Physical Chemistry (associated member of the Center of Interface Science), University of Bremen, Leobener Strasse, 28359 Bremen, Germany.
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Fenske D, Yim WL, Neuendorf S, Hoogestraat D, Greshnykh D, Borchert H, Klüner T, Al-Shamery K. Pitfalls in Interpreting Temperature Programmed Desorption Spectra of Alloys: The CO/CoPt Puzzle. Chemphyschem 2007; 8:654-6. [PMID: 17348053 DOI: 10.1002/cphc.200700004] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Daniela Fenske
- Institute of Pure and Applied Chemistry, Physical Chemistry, Center of Interface Science, Carl-von-Ossietzky Universität Oldenburg, 26111 Oldenburg, Germany
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Lobo A, Borchert H, Talapin D, Weller H, Möller T. Surface oxidation of CdTe nanocrystals—A high resolution core-level photoelectron spectroscopy study. Colloids Surf A Physicochem Eng Asp 2006. [DOI: 10.1016/j.colsurfa.2005.11.068] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Borchert H, Borchert Y, Kaichev VV, Prosvirin IP, Alikina GM, Lukashevich AI, Zaikovskii VI, Moroz EM, Paukshtis EA, Bukhtiyarov VI, Sadykov VA. Nanostructured, Gd-Doped Ceria Promoted by Pt or Pd: Investigation of the Electronic and Surface Structures and Relations to Chemical Properties. J Phys Chem B 2005; 109:20077-86. [PMID: 16853596 DOI: 10.1021/jp051525m] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Nanostructured ceria doped with other rare earth elements is a good oxygen ion conductor, which gives rise to various catalytic applications such as the construction of membranes for syngas production by partial oxidation of methane. This article focuses on the Gd-doped cerium dioxides, which can be modified with Pt or Pd to enhance the reactivity of the lattice oxygen in interaction with methane. The aim of the work is the elucidation of correlations between the structural, electronic, and chemical properties of these nanomaterials. Detailed studies were performed for a series of samples with and without surface modification by noble metals using a complex combination of physicochemical methods: XRD, TEM, CH(4) TPR, XPS, SIMS, and FTIR spectroscopy of adsorbed CO. XPS and TPR data revealed that surface modification with noble metals enhances the reducibility of the doped ceria support, where the effect is more pronounced for Pd than for Pt. The formation of highly cationic Pd species due to strong metal support interactions provides a possible explanation for this behavior. Furthermore, the results obtained in the present work for the Gd-doped ceria system are compared to those obtained previously for the Pr-doped ceria system.
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Affiliation(s)
- Holger Borchert
- Boreskov Institute of Catalysis, SB RAS, Novosibirsk, Russia, and Novosibirsk State University, Novosibirsk, Russia.
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Lobo A, Möller T, Nagel M, Borchert H, Hickey SG, Weller H. Photoelectron Spectroscopic Investigations of Chemical Bonding in Organically Stabilized PbS Nanocrystals. J Phys Chem B 2005; 109:17422-8. [PMID: 16853227 DOI: 10.1021/jp0525888] [Citation(s) in RCA: 100] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The surface structure of organically capped PbS nanocrystals using synchrotron radiation excited core-level photoelectron spectroscopy has been studied. The nanocrystallites prepared by methods of colloidal chemistry have average diameters of 3.1, 3.9, 4.6, and 7.6 nm with narrow size distributions and are stabilized either with oleic acid only or with a combination of trioctylphosphine and oleic acid as ligands. High resolution photoelectron spectroscopy measurements allowed the surface structure to be studied and in particular how the organic ligands bind to the surface of the PbS nanocrystals to be elucidated. The results indicate that the trioctylphosphine ligands passivate only the surface S sites while oleic acid ligands appear to bind mainly to Pb sites.
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Affiliation(s)
- A Lobo
- HASYLAB/DESY, Notkestr. 85, D-22607 Hamburg, Germany.
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Adam S, Talapin DV, Borchert H, Lobo A, McGinley C, de Castro ARB, Haase M, Weller H, Möller T. The effect of nanocrystal surface structure on the luminescence properties: Photoemission study of HF-etched InP nanocrystals. J Chem Phys 2005; 123:084706. [PMID: 16164320 DOI: 10.1063/1.2004901] [Citation(s) in RCA: 97] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
InP nanocrystals with narrow size distribution and mean particle diameter tunable from approximately 2 up to approximately 7 nm were synthesized via the dehalosilylation reaction between InCl3 and tris(trimethylsilyl)phosphine. Specific capping of the nanocrystal surface with a shell of organic ligands protects the nanocrystals from oxidation and provides solubility of the particles in various organic solvents. InP nanocrystals with enhanced photoluminescence (PL) efficiency were obtained from the initial nanocrystals by photoassisted etching of the nanocrystal surface with HF. The resulting PL quantum efficiency of InP nanocrystals dispersed in n-butanol is about three orders of magnitude higher when compared to the nonetched InP samples and approaches approximately 40% at room temperature. High-resolution photoelectron spectroscopy with the use of synchrotron radiation was applied to reveal the changes of the nanocrystal surface responsible for the dramatic improvement of the PL efficiency. The analysis of high-resolution P 2p core-level spectra confirmed significant changes of the nanocrystal surface structure induced by the postpreparative treatments and allowed us to propose the description of the etching mechanism. In the nonetched InP nanocrystals, some surface P atoms generate energy states located inside the band gap which provide nonradiative recombination pathways. Photoassisted treatment of InP nanocrystals with HF results in selective removal of these phosphorous atoms from the nanocrystal surface. The reconstructed surface of the etched InP nanocrystals is terminated mainly with In atoms and is efficiently passivated with tri-n-octylphosphine oxide ligands.
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Affiliation(s)
- S Adam
- HASYLAB/DESY Notkestrasse 85, 22603 Hamburg, Germany
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31
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Strik HM, Borchert H, Fels C, Knauth M, Rienhoff O, Bähr M, Verhey JF. Three-dimensional reconstruction and volumetry of intracranial haemorrhage and its mass effect. Neuroradiology 2005; 47:417-24. [PMID: 15856213 DOI: 10.1007/s00234-005-1373-9] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2004] [Accepted: 01/10/2005] [Indexed: 10/25/2022]
Abstract
Intracerebral haemorrhage still causes considerable disability and mortality. The studies on conservative and operative management are inconclusive, probably due to inexact volumetry of the haemorrhage. We investigated whether three-dimensional (3-D), voxel-based volumetry of the haemorrhage and its mass effect is feasible with routine computed tomography (CT) scans. The volumes of the haemorrhage, ventricles, midline shift, the intracranial volume and ventricular compression in CT scans of 12 patients with basal ganglia haemorrhage were determined with the 3-D slicer software. Indices of haemorrhage and intracranial or ventricular volume were calculated and correlated with the clinical data. The intended measures could be determined with an acceptable intra-individual variability. The 3-D volumetric data tended to correlate better with the clinical course than the conventionally assessed distance of midline shift and volume of haemorrhage. 3-D volumetry of intracranial haemorrhage and its mass effect is feasible with routine CT examination. Prospective studies should assess its value for clinical studies on intracranial space-occupying diseases.
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Affiliation(s)
- H M Strik
- Department of Neurology, Medical School, University of Göttingen, Germany.
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Borchert H, Frolova YV, Kaichev VV, Prosvirin IP, Alikina GM, Lukashevich AI, Zaikovskii VI, Moroz EM, Trukhan SN, Ivanov VP, Paukshtis EA, Bukhtiyarov VI, Sadykov VA. Electronic and Chemical Properties of Nanostructured Cerium Dioxide Doped with Praseodymium. J Phys Chem B 2005; 109:5728-38. [PMID: 16851621 DOI: 10.1021/jp045828c] [Citation(s) in RCA: 150] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Nanostructured doped ceria is a prospective material for catalytic applications such as the construction of membranes with mixed electronic and ionic conductivity for effective syngas production. In this article, the surface properties of nanostructured ceria doped with praseodymium have been studied by X-ray photoelectron spectroscopy, secondary ion mass spectrometry, and Fourier transform infrared spectroscopy of adsorbed carbon monoxide. The effects of supporting 1.4 wt % Pt as well as structural changes upon the reduction of the samples with methane have been investigated. While in samples without supported platinum, mainly praseodymium cations are reduced in a methane atmosphere; stronger reduction of cerium cations was found in the case of surface modification with Pt. The structural differences correlate with results from temperature-programmed reaction experiments with methane. Explanations are discussed in terms of different reaction mechanisms.
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Affiliation(s)
- Holger Borchert
- Boreskov Institute of Catalysis SB RAS and Novosibirsk State University, Novosibirsk, Russia
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Borchert H, Shevchenko EV, Robert A, Mekis I, Kornowski A, Grübel G, Weller H. Determination of nanocrystal sizes: a comparison of TEM, SAXS, and XRD studies of highly monodisperse CoPt3 particles. Langmuir 2005; 21:1931-1936. [PMID: 15723491 DOI: 10.1021/la0477183] [Citation(s) in RCA: 331] [Impact Index Per Article: 17.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
One of the most fundamental tasks in nanoscience is the accurate determination of particle sizes. Various methods have been developed to elucidate the mean particle diameter and the standard deviation for an ensemble of nanocrystals. However, good agreement between the results from different methods is not always encountered in the literature. In this study, we investigate colloidally prepared, highly monodisperse CoPt3 nanoparticles by transmission electron microscopy (TEM), small-angle X-ray scattering (SAXS), and powder X-ray diffraction (XRD). The results are compared in order to examine to which extent agreement is obtained by the different techniques when applied to small nanocrystals in the size range below 10 nm. In particular, the applicability of the simple Scherrer formula for size determination from the broadening of XRD reflections is checked. When the different techniques are correctly applied, the results from all methods are in good agreement.
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Affiliation(s)
- Holger Borchert
- Institute of Physical Chemistry, Grindelallee 117, 20146 Hamburg, Germany.
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Borchert H, Baerns M. Kinetische Charakterisierung von mit Cs2SO4dotierten V2O5-Fe2O3-Katalysatoren für die Fluoren-Oxidation zu Fluorenon. CHEM-ING-TECH 2004. [DOI: 10.1002/cite.330640721] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Borchert H, Gayko G, Baerns M. Einfluß der Sauerstoffanionenleitfähigkeit und der Basizität von Metalloxidkatalysatoren auf die Selektivität der oxidativen Methankupplung zu höheren Kohlenwasserstoffen. CHEM-ING-TECH 2004. [DOI: 10.1002/cite.330660308] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Kömpe K, Borchert H, Storz J, Lobo A, Adam S, Möller T, Haase M. Mit einer Quantenausbeute von 70 % grün lumineszierende CePO4:Tb-Nanopartikel mit einer Schale aus LaPO4. Angew Chem Int Ed Engl 2003. [DOI: 10.1002/ange.200351943] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Kömpe K, Borchert H, Storz J, Lobo A, Adam S, Möller T, Haase M. Green-Emitting CePO4:Tb/LaPO4 Core–Shell Nanoparticles with 70 % Photoluminescence Quantum Yield. Angew Chem Int Ed Engl 2003; 42:5513-6. [PMID: 14618592 DOI: 10.1002/anie.200351943] [Citation(s) in RCA: 381] [Impact Index Per Article: 18.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Karsten Kömpe
- Institute of Physical Chemistry, University of Hamburg, Bundesstrasse 45, 20 146 Hamburg, Germany
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Borchert H, Talapin DV, Gaponik N, McGinley C, Adam S, Lobo A, Möller T, Weller H. Relations between the Photoluminescence Efficiency of CdTe Nanocrystals and Their Surface Properties Revealed by Synchrotron XPS. J Phys Chem B 2003. [DOI: 10.1021/jp0352884] [Citation(s) in RCA: 179] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Holger Borchert
- Institute of Physical Chemistry, University of Hamburg, Bundesstr. 45, 20146 Hamburg, Germany, and Hamburger Synchrotronstrahlungslabor HASYLAB at DESY, Notkestr. 85, 22603 Hamburg, Germany
| | - Dmitri V. Talapin
- Institute of Physical Chemistry, University of Hamburg, Bundesstr. 45, 20146 Hamburg, Germany, and Hamburger Synchrotronstrahlungslabor HASYLAB at DESY, Notkestr. 85, 22603 Hamburg, Germany
| | - Nikolai Gaponik
- Institute of Physical Chemistry, University of Hamburg, Bundesstr. 45, 20146 Hamburg, Germany, and Hamburger Synchrotronstrahlungslabor HASYLAB at DESY, Notkestr. 85, 22603 Hamburg, Germany
| | - Colm McGinley
- Institute of Physical Chemistry, University of Hamburg, Bundesstr. 45, 20146 Hamburg, Germany, and Hamburger Synchrotronstrahlungslabor HASYLAB at DESY, Notkestr. 85, 22603 Hamburg, Germany
| | - Sorin Adam
- Institute of Physical Chemistry, University of Hamburg, Bundesstr. 45, 20146 Hamburg, Germany, and Hamburger Synchrotronstrahlungslabor HASYLAB at DESY, Notkestr. 85, 22603 Hamburg, Germany
| | - Arun Lobo
- Institute of Physical Chemistry, University of Hamburg, Bundesstr. 45, 20146 Hamburg, Germany, and Hamburger Synchrotronstrahlungslabor HASYLAB at DESY, Notkestr. 85, 22603 Hamburg, Germany
| | - Thomas Möller
- Institute of Physical Chemistry, University of Hamburg, Bundesstr. 45, 20146 Hamburg, Germany, and Hamburger Synchrotronstrahlungslabor HASYLAB at DESY, Notkestr. 85, 22603 Hamburg, Germany
| | - Horst Weller
- Institute of Physical Chemistry, University of Hamburg, Bundesstr. 45, 20146 Hamburg, Germany, and Hamburger Synchrotronstrahlungslabor HASYLAB at DESY, Notkestr. 85, 22603 Hamburg, Germany
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Borchert H, Talapin DV, McGinley C, Adam S, Lobo A, de Castro ARB, Möller T, Weller H. High resolution photoemission study of CdSe and CdSe/ZnS core-shell nanocrystals. J Chem Phys 2003. [DOI: 10.1063/1.1580096] [Citation(s) in RCA: 69] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Ganslandt O, Mueller R, Mueller W, Borchert H, Grabenbauer GG. Simple invasive fixation device for fractionated stereotactic LINAC based radiotherapy. Acta Neurochir (Wien) 2003; 145:289-94; discussion 294. [PMID: 12748889 DOI: 10.1007/s00701-003-0002-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
BACKGROUND The aim of this study was to develop a relocatable fixation device for linear accelerator (LINAC) based fractionated stereotactic radiotherapy. METHOD The device consists of a CT- and MRI-compatible stereotactic frame, monocortical titan bone screws, four frame-posts with a lock for the fixation pins and a modified head clamp with additional arms that allows the exact and rigid placement of the frame in the desired final position prior to the final placement of the bone screws. By simply disconnecting the lock from the posts, the frame can be dismounted after treatment planning and after each treatment session. The accuracy of reposition was assessed prospectively, using phantom studies and also by comparison of isocenter movements during fractionated radiotherapy in 10 patients with an intracranial lesion. FINDINGS No adverse events were seen after the surgical procedure and the screws were well tolerated throughout the course of treatment. The mean isocenter shifts observed during phantom reposition studies were x=0.05 mm, y=-0.32 mm, z=0.18 mm and the mean isocenter shifts during fractionated treatment were x=0.67 mm, y=0.65 mm, z=0.44 mm. INTERPRETATION This new fixation device provides excellent accuracy of reposition during stereotactic radiotherapy. It appears superior to non-invasive, mask fixation techniques. Safety margins as small as 1-1.5 mm may therefore be sufficient for this method of stereotactic radiotherapy.
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Affiliation(s)
- O Ganslandt
- Department of Neurosurgery, University of Erlangen-Nürnberg, Germany
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Borchert H, Dorfs D, McGinley C, Adam S, Möller T, Weller H, Eychmüller A. Photoemission Study of Onion Like Quantum Dot Quantum Well and Double Quantum Well Nanocrystals of CdS and HgS. J Phys Chem B 2003. [DOI: 10.1021/jp027485t] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Holger Borchert
- Institute of Physical Chemistry, University of Hamburg, Bundesstr. 45, 20146 Hamburg, Germany, and Hamburger Synchrotronstrahlungslabor HASYLAB at DESY, Notkestr. 85, 22603 Hamburg, Germany
| | - Dirk Dorfs
- Institute of Physical Chemistry, University of Hamburg, Bundesstr. 45, 20146 Hamburg, Germany, and Hamburger Synchrotronstrahlungslabor HASYLAB at DESY, Notkestr. 85, 22603 Hamburg, Germany
| | - Colm McGinley
- Institute of Physical Chemistry, University of Hamburg, Bundesstr. 45, 20146 Hamburg, Germany, and Hamburger Synchrotronstrahlungslabor HASYLAB at DESY, Notkestr. 85, 22603 Hamburg, Germany
| | - Sorin Adam
- Institute of Physical Chemistry, University of Hamburg, Bundesstr. 45, 20146 Hamburg, Germany, and Hamburger Synchrotronstrahlungslabor HASYLAB at DESY, Notkestr. 85, 22603 Hamburg, Germany
| | - Thomas Möller
- Institute of Physical Chemistry, University of Hamburg, Bundesstr. 45, 20146 Hamburg, Germany, and Hamburger Synchrotronstrahlungslabor HASYLAB at DESY, Notkestr. 85, 22603 Hamburg, Germany
| | - Horst Weller
- Institute of Physical Chemistry, University of Hamburg, Bundesstr. 45, 20146 Hamburg, Germany, and Hamburger Synchrotronstrahlungslabor HASYLAB at DESY, Notkestr. 85, 22603 Hamburg, Germany
| | - Alexander Eychmüller
- Institute of Physical Chemistry, University of Hamburg, Bundesstr. 45, 20146 Hamburg, Germany, and Hamburger Synchrotronstrahlungslabor HASYLAB at DESY, Notkestr. 85, 22603 Hamburg, Germany
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Talapin DV, Gaponik N, Borchert H, Rogach AL, Haase M, Weller H. Etching of Colloidal InP Nanocrystals with Fluorides: Photochemical Nature of the Process Resulting in High Photoluminescence Efficiency. J Phys Chem B 2002. [DOI: 10.1021/jp026380n] [Citation(s) in RCA: 183] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Dmitri V. Talapin
- Institute of Physical Chemistry, University of Hamburg, 20146 Hamburg, Germany
| | - Nikolai Gaponik
- Institute of Physical Chemistry, University of Hamburg, 20146 Hamburg, Germany
| | - Holger Borchert
- Institute of Physical Chemistry, University of Hamburg, 20146 Hamburg, Germany
| | - Andrey L. Rogach
- Institute of Physical Chemistry, University of Hamburg, 20146 Hamburg, Germany
| | - Markus Haase
- Institute of Physical Chemistry, University of Hamburg, 20146 Hamburg, Germany
| | - Horst Weller
- Institute of Physical Chemistry, University of Hamburg, 20146 Hamburg, Germany
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Ahrens J, Borchert H, Zieger A, Zieger B. A compton spectrometer for the energy range between 10 and 300 MeV and its application to photon flux and photon absorption measurements. ACTA ACUST UNITED AC 1973. [DOI: 10.1016/0029-554x(73)90533-8] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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G�nzler H, Waldmeier M, St�nkel D, Borchert H, Scheffer F. Buchbesprechungen. Naturwissenschaften 1963. [DOI: 10.1007/bf00689253] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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45
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Samelson K, Flammersfeld A, Hoffmann KW, Borchert H. Besprechungen. Naturwissenschaften 1960. [DOI: 10.1007/bf00633772] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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46
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48
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Einstein O, Borchert H. �ber eine einfache Konzentrationsbestimmung kolloider L�sungen. (Auswertung des Tyndalleffekts.). Naturwissenschaften 1929. [DOI: 10.1007/bf01505861] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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