Article
Chemistry, Physical
Maciej J. Winiarski
Summary: This study investigated the electronic structures of ternary alloys of group III and rare earth nitrides, revealing that the introduction of rare earth ions can affect the band gap width. The findings suggest potential applications of these materials, encouraging further experimental investigations.
Article
Chemistry, Physical
Matthias H. Richter, Elizabeth A. Peterson, Lan Zhou, Aniketa A. Shinde, Paul F. Newhouse, Qimin Yan, Sean W. Fackler, Junko Yano, Jason K. Cooper, Kristin A. Persson, Jeffrey B. Neaton, John M. Gregoire
Summary: Research has identified a wide range of band gap energy in M-V-O compounds for photoanode materials, with tunable electronic structure prediction and potential for high-efficiency metal oxide photoanodes. The contribution of oxygen vacancies to the electronic structure has been confirmed to guide future development of efficient photoanodes for solar fuel technology.
CHEMISTRY OF MATERIALS
(2021)
Article
Materials Science, Multidisciplinary
Bingfeng Cui, Yu Gao, Xiaopeng Han, Wenbin Hu
Summary: Sn coating loaded on copper foil is used to guide the uniform zinc deposition and improve the performance of zinc metal batteries.
JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY
(2022)
Article
Computer Science, Information Systems
Sang-Hwa Jeon, Ziyuan Wang, Kyeong-Ho Seo, Junhao Feng, Xue Zhang, Jaehoon Park, Jin-Hyuk Bae
Summary: Controlling the temperature of the pre-annealing stage is crucial for the evaporation of solvent in solution-processed ZTO TFTs, leading to enhanced electrical performance and stability. Increasing the temperature can effectively remove organic defects, but excessive temperatures may result in structural defects.
Article
Chemistry, Multidisciplinary
Deqiang Yin, Chaochao Dun, Huisheng Zhang, Zheng Fu, Xiang Gao, Xianliang Wang, David J. Singh, David L. Carroll, Yang Liu, Mark T. Swihart
Summary: Advances in crystal phase and shape engineering of binary or ternary copper telluride nanocrystals have been achieved using a colloidal hot-injection approach. The morphology of the NCs can be controlled by preferential growth of specific crystalline facets. In addition, temperature dependent thermoelectric properties of metal telluride nanostructure thin films have been studied.
Article
Chemistry, Multidisciplinary
Chen Shen, Tianshu Li, Yixuan Zhang, Ruiwen Xie, Teng Long, Nuno M. Fortunato, Fei Liang, Mian Dai, Jiahong Shen, Christopher M. Wolverton, Hongbin Zhang
Summary: Chalcogenides, particularly ternary chalcogenides, have potential applications in optoelectronics, thermoelectrics, transparent contacts, and thin-film transistors. Despite the relatively low number of successfully synthesized compounds, there are numerous unexplored chalcogenides with fascinating physical characteristics. In this study, a systematic high-throughput screening process combined with first-principles calculations was implemented to study ternary chalcogenides and generate a large computational material database. Machine learning models were used to predict the thermodynamic stability of novel materials, and the electronic structures and performance of stable candidates were evaluated.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Chemistry, Multidisciplinary
S. T. Yussuf, K. V. Mokwebo, K. C. Januarie, M. Oranzie, E. I. Iwuoha
Summary: Recently, kesterite (CZTS) has been considered as a promising alternative material for low-cost thin film solar cells due to its high absorption coefficient, direct band gap, natural abundance, and low toxicity. However, the efficiency of CZTS solar cells is still relatively low compared to silicon, which hinders its commercialization. Therefore, developing new materials with improved optical and photovoltaic properties is encouraged.
MATERIALS TODAY CHEMISTRY
(2023)
Article
Chemistry, Physical
Neville J. Cory, Eran Visser, Jessica Chamier, Juliet Sackey, Franscious Cummings, Mahabubur Chowdhury
Summary: In this study, a CuO thin film sensor was prepared using electrodeposition method for photo electrochemical glucose detection, showing good amperometric performance and a wide linear range under light conditions. The band gap of photoactive CuO thin film can be tuned by etching in NH3 solution, and the oxidation of glucose is found to be an irreversible electron transfer process controlled by diffusion.
APPLIED SURFACE SCIENCE
(2022)
Article
Materials Science, Multidisciplinary
Sooji Nam, Su-Jae Lee, Jae-Eun Pi, Jong-Heon Yang, Chi-Sun Hwang, Sung Haeng Cho
Summary: The development of high-performance p-type metal-oxide semiconductors has opened up new possibilities for transparent, flexible, and low-power integrated circuits. The fabrication of solution-processed p-type metal-oxide thin-film transistors with excellent device performance at low temperatures using a novel material has been reported. The optimized K-doped SnO TFTs exhibit outstanding electrical performance, showing potential for low-cost flexible p-type metal-oxide electronics.
PHYSICA STATUS SOLIDI A-APPLICATIONS AND MATERIALS SCIENCE
(2021)
Article
Chemistry, Multidisciplinary
Zachary R. Lindsey, Malachi West, Peter Jacobson, John Robert Ray
Summary: Compared to Si, GaAs has advantages such as high carrier mobility and energy conversion efficiency, making it a leading competitor in optoelectronics and solar energy conversion. This research demonstrates the electrodeposition and controlled alloying of polycrystalline InxGa1-xAs films at ambient pressure and near-room temperature using the electrochemical liquid-liquid-solid (ec-LLS) process.
CRYSTAL GROWTH & DESIGN
(2022)
Article
Environmental Sciences
Boubaker Youbi, Youssef Lghazi, Mohammed Ait Himi, Aziz Aynaou, Jihane Bahar, Chaimaa El Haimer, Abdessamad Ouedrhiri, Ahmed Sahlaoui, Itto Bimaghra
Summary: Zinc telluride (ZnTe) is a promising material for optoelectronic and photovoltaic device applications due to its optimal characteristics in terms of environmental compatibility, abundance, and photoactivity. This study revealed that the electrodeposition of ZnTe on an indium tin oxide substrate is a quasi-reversible reaction controlled by diffusion, following the nucleation and growth mechanism proposed by Scharifker and Hill. The crystallographic structure of the ZnTe films was found to be cubic, and the films exhibited good homogeneity. Optical measurements showed a direct energy gap of 2.39 eV for the deposited films.
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
(2023)
Article
Physics, Multidisciplinary
Yunlong Li, Chaozhi Huang, Guohua Wang, Jiayuan Hu, Shaofeng Duan, Chenhang Xu, Qi Lu, Qiang Jing, Wentao Zhang, Dong Qian
Summary: The study compared experimental results with first-principles calculations for GeBi2Te4, SnBi2Te4, and Sn0.571Bi2.286Se4, confirming their topological insulator properties. The experimental observations indicated larger energy gaps in the bulk states compared to theoretical calculations.
Review
Biochemistry & Molecular Biology
Hong Yong Sohn, Arun Murali
Summary: This article reviews and summarizes recent work in this laboratory on the synthesis of advanced transparent conducting oxide nanopowders using plasma. The process involves selecting suitable precursors, injecting them into a non-transferred thermal plasma, vaporizing them, and forming nanosized oxide particles through vapor-phase reactions. The thermal plasma process shows great potential as an efficient technique for synthesizing oxide nanopowders.
Article
Chemistry, Inorganic & Nuclear
James D. Parish, Michael W. Snook, Andrew L. Johnson
Summary: A family of tin(ii) heteroleptic complexes and homoleptic systems were successfully synthesized and structurally characterized. NMR spectroscopy and single-crystal X-ray diffraction studies were used for comprehensive characterization. Thermal behavior of the complexes was investigated to determine their suitability as ALD precursors for SnO thin films deposition.
DALTON TRANSACTIONS
(2021)
Article
Nanoscience & Nanotechnology
Pravinraj Selvaraj, Shi-Jie Chen, Yu-Han Cheng, Ming-Han Chi, Sreeshyam Adat, Yu-Wu Wang
Summary: This study investigates the growth of ZnO nanowires on ZTO-based FETs to develop a superior photosensitive self-powered photodetector. The resulting device exhibits high sensitivity and long carrier lifetime. Highly sensitive photodetectors based on ZTO/ZnO NW transistors are expected to have critical applications in various fields.
ACS APPLIED NANO MATERIALS
(2023)
Article
Instruments & Instrumentation
Lothar Weinhardt, Ralph Steininger, Dagmar Kreikemeyer-Lorenzo, Stefan Mangold, Dirk Hauschild, David Batchelor, Thomas Spangenberg, Clemens Heske
Summary: The X-SPEC beamline at KIT's Synchrotron is a high-flux spectroscopy beamline for electron and X-ray spectroscopy, covering a wide photon energy range. It features various elements such as an undulator, monochromators, and mirror pairs for energy range from 70 eV to 15 keV. The beam can be focused into two experimental stations for solid samples under ultra-high-vacuum conditions and in situ studies under ambient conditions, utilizing techniques like XAS, EXAFS, PES, HAXPES, XES, and RIXS.
JOURNAL OF SYNCHROTRON RADIATION
(2021)
Article
Chemistry, Physical
Regan G. Wilks, Axel Erbing, Golnaz Sadoughi, David E. Starr, Evelyn Handick, Frank Meyer, Andreas Benkert, Marcella Iannuzzi, Dirk Hauschild, Wanli Yang, Monika Blum, Lothar Weinhardt, Clemens Heske, Henry J. Snaith, Michael Odelius, Marcus Baer
Summary: The organic component of CH3NH3PbI3-xClx perovskites exhibits electronic hybridization with the inorganic framework via H-bonding between N and I sites. Femtosecond dynamics induced by core excitation strongly affect the measured X-ray emission spectra and resonant inelastic soft X-ray scattering of the organic components. Excited-state dynamics must be considered in spectroscopic studies of this perovskite solar cell material, indicating new avenues for probing its electronic structure.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2021)
Article
Energy & Fuels
D. Hauschild, S. J. Wachs, W. Kogler, L. Seitz, J. Carter, T. Schnabel, B. Krause, M. Blum, W. Yang, E. Ahlswede, C. Heske, L. Weinhardt
Summary: A carbon-rich layer at the back-contact interface of a solution-processed CZTSSe absorber was investigated, revealing a detailed chemical structure consisting of carbon, selenium, and sulfur. Selenium was found as elemental inclusions, possibly due to incomplete reaction during absorber production, while sulfur was traced back to residuals from the aqueous ATGL solution. Additionally, S-Mo bonds were found underneath the carbon-rich layer at the Mo back contact.
IEEE JOURNAL OF PHOTOVOLTAICS
(2021)
Article
Nanoscience & Nanotechnology
Somayeh Moghadamzadeh, Ihteaz M. Hossain, Moritz Loy, David Benedikt Ritzer, Hang Hu, Dirk Hauschild, Adrian Mertens, Jan-Philipp Becker, Amir A. Haghighirad, Erik Ahlswede, Lothar Weinhardt, Uli Lemmer, Bahram Abdollahi Nejand, Ulrich W. Paetzold
Summary: This study demonstrates a significant increase in photocurrent for all-perovskite tandem solar cells by removing the hole-transport layer and using hydrogen-doped indium oxide electrodes. The IO:H-based solar cells achieved a higher power conversion efficiency compared to the commonly used ITO, highlighting the potential of utilizing this material in photovoltaic applications.
ACS APPLIED MATERIALS & INTERFACES
(2021)
Article
Chemistry, Analytical
Lothar Weinhardt, Dirk Hauschild, Ralph Steininger, Nan Jiang, Monika Blum, Wanli Yang, Clemens Heske
Summary: The chemical and electronic structures of 15 different sulfates were studied using S L-2, L-3 soft X-ray emission spectroscopy (XES). The sulfur L-2, L-3 XES spectra of sulfates are distinct from those of other sulfur compounds, making XES a powerful technique for sulfate detection. Subtle but distinct differences between the spectra of sulfates with different cations are observed, allowing for further differentiation of specific compounds. Most notably, the position and width of the emission from S 3s derived bands systematically vary for different compounds, which can be understood through electronic structure and spectral calculations based on density functional theory.
ANALYTICAL CHEMISTRY
(2021)
Article
Nanoscience & Nanotechnology
Dirk Hauschild, Linsey Seitz, Saba Gharibzadeh, Ralph Steininger, Nan Jiang, Wanli Yang, Ulrich Wilhelm Paetzold, Clemens Heske, Lothar Weinhardt
Summary: The impact of BABr surface treatment on double-cation perovskite thin film was studied, revealing modifications in the surface environment which can be crucial for optimizing the treatment and enhancing the performance of perovskite solar cells.
ACS APPLIED MATERIALS & INTERFACES
(2021)
Article
Chemistry, Physical
Chinnathambi Kamal, Dirk Hauschild, Linsey Seitz, Ralph Steininger, Wanli Yang, Clemens Heske, Lothar Weinhardt, Michael Odelius
Summary: The electronic structures of four precursors for organic-inorganic hybrid perovskites were studied using X-ray emission spectroscopy, highlighting the stronger interaction between the methylammonium cation and the chlorine anion compared to the iodine anion. Detailed theoretical analysis emphasized the significance of ultrafast proton dynamics in core-excited states.
JOURNAL OF PHYSICAL CHEMISTRY C
(2021)
Article
Materials Science, Coatings & Films
Dirk Hauschild, Ralph Steininger, Dimitrios Hariskos, Wolfram Witte, Sven Tougaard, Clemens Heske, Lothar Weinhardt
Summary: The study analyzes the inelastic background of hard x-ray photoelectron spectroscopy data to provide depth-resolved information on the CdS/CIGSe layer structure. By analyzing core-level peaks and inelastic background, the study accurately determines the CdS film thickness at the CdS/CIGSe interface, observing lateral variations in thickness for thinner CdS films. Additionally, small amounts of Se and process-related Rb are detected in a thin surface layer of all investigated CdS films.
JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A
(2021)
Article
Materials Science, Multidisciplinary
Alexander Eslam, Roland Wuerz, Dirk Hauschild, Lothar Weinhardt, Wolfram Hempel, Michael Powalla, Clemens Heske
Summary: The influence of post-deposition treatments with NaF and KF on Cu(In,Ga)Se2 thin-film solar cell absorbers was studied at different substrate temperatures. Both treatments significantly improved cell efficiency, with the highest conversion efficiency achieved with NaF PDT at a high temperature. KF treatment led to reduced efficiency at low temperature due to the formation of a Cu-Se secondary phase at the CIGSe surface.
Article
Chemistry, Physical
Frank Meyer, Dirk Hauschild, Andreas Benkert, Monika Blum, Wanli Yang, Friedrich Reinert, Clemens Heske, Michael Zharnikov, Lothar Weinhardt
Summary: This study investigates the electronic structure of proline in solid state and aqueous solution using X-ray emission spectroscopy and resonant inelastic soft X-ray scattering. The results show that while the carboxyl group of proline has a similar electronic structure to other amino acids and acetic acid, the electronic structure of the amino group is significantly different and influenced by the ring structure of proline.
JOURNAL OF PHYSICAL CHEMISTRY B
(2022)
Article
Chemistry, Multidisciplinary
Lothar Weinhardt, Dirk Hauschild, Oliver Fuchs, Ralph Steininger, Nan Jiang, Monika Blum, Jonathan D. Denlinger, Wanli Yang, Eberhard Umbach, Clemens Heske
Summary: The sulfur L2,3 X-ray emission spectra of alkaline earth metal sulfides have been investigated. The results show distinct spectral shapes for different compounds, and the spectral calculations based on density functional theory provide an accurate description of the spectral shapes in the upper valence band region. Semi-Auger decays involving configuration interaction produce strong satellites on the low energy side of sulfur 3s-*2p transition, which become more intense as the bonding character becomes more ionic. These satellites can be used as a specific spectral fingerprint for speciation analysis.
Article
Chemistry, Physical
Clemens Heske, James C. Carter, Dirk Hauschild, Lothar Weinhardt, Kimberly Horsley, Dimitrios Hariskos, Nicolas Gaillard
Summary: This article presents the electronic surface level positions of different chalcopyrite [Cu(In,Ga)(S,Se)2] thin-film absorbers and discusses their suitability for photoelectrochemical (PEC) water splitting. Suitable band edge energies (CBM and VBM) at the electrode surfaces are necessary for efficient PEC water splitting to enable hydrogen and oxygen evolution. Strategies to optimize chalcopyrite PEC devices for solar water splitting with respect to redox potentials are derived through studying various chalcopyrite variants in growth process, composition, stoichiometry, and surface treatment.
JOURNAL OF PHYSICAL CHEMISTRY C
(2023)
Article
Energy & Fuels
Dirk Hauschild, Mary Blankenship, Amandee Hua, Ralph Steininger, Patrick Eraerds, Thomas Niesen, Thomas Dalibor, Wanli Yang, Clemens Heske, Lothar Weinhardt
Summary: The chemical and electronic structure of the interface between a sputter-deposited Zn(O,S) buffer layer and an industrial Cu(In,Ga)(S,Se)(2) (CIGSSe) absorber for thin-film solar cells was investigated using various spectroscopic techniques. It was found that the CIGSSe absorber surface band gap significantly increased compared to bulk-sensitive methods. The measurements also showed the presence of S-Zn and S-O bonds in the Zn(O,S) layer, and an enhanced carrier separation at the interface.
Article
Nanoscience & Nanotechnology
Elizaveta Pyatenko, Dirk Hauschild, Vladyslav Mikhnych, Raju Edla, Ralph Steininger, Dimitrios Hariskos, Wolfram Witte, Michael Powalla, Clemens Heske, Lothar Weinhardt
Summary: In this study, the chemical structure of the Cu(In,Ga)Se-2 (CIGSe) thin-film solar cell absorber surfaces and their interface with a Ga2O3 buffer layer were investigated. The effects of different treatments on the chemical composition and impurities at the absorber surface were analyzed using various spectroscopic techniques. The results suggest that a specific rinsing step can effectively remove impurities and alter the chemical composition of the absorber layer.
ACS APPLIED MATERIALS & INTERFACES
(2023)
Article
Chemistry, Multidisciplinary
Teoman Taskesen, Devendra Pareek, Dirk Hauschild, Alan Haertel, Lothar Weinhardt, Wanli Yang, Timo Pfeiffelmann, David Nowak, Clemens Heske, Levent Gutay
Summary: This study presents a novel approach to introduce a [S]/([S] + [Se]) grading for Cu2ZnSn(S,Se)(4) solar cells by creating a fast sulfurization reaction on the surface of pure selenide kesterite absorbers using highly reactive H2S gas and high sulfurization temperatures in a rapid flash-type process. Various analysis techniques were used to gain depth-varied information on the [S]/([S] + [Se]) ratio and discuss the impact of different process parameter variations on the material and device properties. The results demonstrate the potential of the developed process to generate a steep gradient of sulfur mainly confined to the surface region of the absorber film.
