Article
Chemistry, Multidisciplinary
Nataliya Vorobyeva, Marina Rumyantseva, Vadim Platonov, Darya Filatova, Artem Chizhov, Artem Marikutsa, Ivan Bozhev, Alexander Gaskov
Summary: This study investigates the impact of tin doping on Gallium(III) oxide for high temperature gas sensors, with a focus on its effect on material conductivity, phase content, microstructure, adsorption sites, and gas sensor properties. The introduction of tin decreases the crystallite size of Ga2O3 and increases the formation temperature of beta-Ga2O3, leading to non-monotonous sensor responses to CO and NH3.
Article
Chemistry, Physical
Hojoon Lim, Dongwoo Kim, Su Yeon Cha, Bongjin Simon Mun, Do Young Noh, Hyon Chol Kang
Summary: The evolution of the structural and chemical properties of non-stoichiometric amorphous Ga2O3-x thin films during post-annealing in an atmospheric environment was investigated. The results showed that the films crystallized into a mixture of alpha and beta phases, achieving a stoichiometric state. The optical bandgap increased with the increase of annealing temperature.
APPLIED SURFACE SCIENCE
(2022)
Article
Chemistry, Analytical
A. Almaev, V. Nikolaev, N. N. Yakovlev, P. N. Butenko, S. Stepanov, A. Pechnikov, M. P. Scheglov, E. Chernikov
Summary: The gas sensing properties of Pt/α-Ga2O3:Sn/Pt metal-semiconductor-metal (MSM) structures based on epitaxial films of α-Ga2O3 with Pt contacts were investigated. The structures showed high sensitivity to H-2, and it was found that the Pt contacts and Sn doping level played a key role in determining the hydrogen sensing properties. The sensitivity to H-2 was attributed to the modulation of the Schottky barrier height between Pt and α-Ga2O3:Sn.
SENSORS AND ACTUATORS B-CHEMICAL
(2022)
Article
Engineering, Electrical & Electronic
Rekha Pilliadugula, N. Gopalakrishnan
Summary: In this study, Sn was doped into the β-Ga2O3 lattice through hydrothermal method at different concentrations, showing enhanced NH3 sensing capabilities in the 2% doped sample. The research also highlighted the sensitivity of the doped samples to humidity and oxygen levels.
MATERIALS SCIENCE IN SEMICONDUCTOR PROCESSING
(2021)
Article
Chemistry, Physical
Sunjae Kim, Heejoong Ryou, Jeonghyun Moon, In Gyu Lee, Wan Sik Hwang
Summary: In this study, Al and In dopants are codoped in B-Ga2O3 nanostructures via hydrothermal synthesis. It is found that the codoping of Al and In atoms can reduce the mechanical strain induced in the B-Ga2O3 nanostructures compared to single-dopant doping, leading to enhanced photocatalytic activity at higher dopant concentrations.
JOURNAL OF ALLOYS AND COMPOUNDS
(2023)
Article
Engineering, Electrical & Electronic
Vesna Lojpur, Maximilian Joschko, Christina Graf, Nadezda Radmilovic, Mirjana Novakovic, Ivana Validzic
Summary: Non-doped and iodine-tin-doped Sb2S3 nanoparticles were prepared and characterized using HRTEM, EDX, reflectance spectra, and XRPD, with XPS measurements providing additional insights into the incorporation of dopant ions in the lattice. The presence of desired elements, variations in bandgaps, and shifts in valence bands suggest successful doping processes, highlighting the importance of studying both amorphous and crystalline samples in material characterization.
MATERIALS SCIENCE IN SEMICONDUCTOR PROCESSING
(2022)
Article
Crystallography
Jin Cao, Liang Chen, Xin Chen, Yu Zhu, Jianqi Dong, Baoyu Wang, Miao He, Xingfu Wang
Summary: The study focuses on improving the performance of the a-Ga2O3/p-Si photodetector by oxygen plasma treatment, reducing the concentration of oxygen vacancies, decreasing dark current, increasing responsivity, and enabling the detector to operate well at 0V bias. The response speed is attributed to the reduction of the Schottky barrier between a-Ga2O3 and the ITO electrode through oxygen plasma treatment.
Article
Nanoscience & Nanotechnology
Ymir K. Frodason, Patryk P. Krzyzaniak, Lasse Vines, Joel B. Varley, Chris G. Van de Walle, Klaus Magnus H. Johansen
Summary: The diffusion of the n-type dopant Sn in beta-Ga2O3 was studied using secondary-ion mass spectrometry combined with hybrid functional calculations. It was found that Ga vacancies mediate the migration of Sn through the formation and dissociation of intermittent mobile VGaSnGa complexes. The migration barrier for the VGaSnGa complex was determined to be 3.0 +/- 0.4 eV, consistent with theoretical predictions using the nudged elastic band method.
Article
Chemistry, Multidisciplinary
Yi Shen, Hong-Ping Ma, Lin Gu, Jie Zhang, Wei Huang, Jing-Tao Zhu, Qing-Chun Zhang
Summary: In this work, atomic level doping of Sn into Ga2O3 films was achieved using a plasma-enhanced atomic layer deposition method. The study investigated the effects of doping on the chemical state, microstructure, optical properties, energy band alignment, and electrical properties of the films. The results provide valuable insights for the design and application of Ga2O3 film-based transparent devices.
Article
Chemistry, Physical
Jiehai Peng, Yuan Yuan, Wuhua Yuan, Kun Peng
Summary: In this study, urchin-like Co3O4 microspheres were synthesized and oxygen vacancies and phosphorus doping were introduced to adjust the electronic structure, increasing catalytic activity, improving adsorption energy of intermediates, and activating more active sites for the catalytic reaction. Additionally, Co3O4-Ov and Co3O4-P catalysts demonstrated excellent performance in OER and HER, with an electrolytic cell only needing 1.58 V to achieve 20 mA cm-2 for overall water splitting.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2021)
Article
Nanoscience & Nanotechnology
Rui Zhu, Huili Hang, Sigui Hu, Yan Wang, Zengxia Mei
Summary: Developing low-energy optoelectronic synaptic devices using amorphous-Ga2O3 has successfully mimicked basic synaptic functions, achieved noise suppression capability, and approached the energy consumption level of biological synapses. The synergetic modulation effect of optical and electric fields on oxygen vacancy defects plays a key role in the performance of a-Ga2O3 synapses.
ADVANCED ELECTRONIC MATERIALS
(2022)
Article
Materials Science, Multidisciplinary
Haonan Dong, Yi Yang, Jing Zhu, Xiaolei Zhu, Fayu Wu, Chongyi Wei, Maolin Sun
Summary: The evolvement of ternary Zn-O-Sn systems were studied through different methods including oxygen-controlled sputtering, oxygensubtracted annealing, and introduction of fluorine. The results showed that the selection and formation of different phases in the Zn-O-Sn systems could be controlled by adjusting the oxygen content. The presence of oxygen favored the growth of dual-phase Zn2SnO4/SnO2, while the absence of oxygen or the presence of fluorine favored the growth of amorphous ZnSnO3, which could further crystallize to perovskite ZnSnO3 under certain conditions. Compared to the dual-phase Zn2SnO4/SnO2, the single-phase amorphous ZnSnO3 with more oxygen vacancies exhibited better optical and electrical properties for H-2 sensing.
MATERIALS TODAY COMMUNICATIONS
(2023)
Article
Materials Science, Ceramics
Chen Wang, Wei-Hang Fan, Yu-Chao Zhang, Pin-Chun Kang, Wan-Yu Wu, Dong-Sing Wuu, Shui-Yang Lien, Wen-Zhang Zhu
Summary: This study investigated the properties of Sn-doped Ga2O3 films deposited on sapphire substrates through RF magnetron sputtering at different oxygen flow ratios. In situ optical emission spectroscopy was used to monitor the plasma radicals generated during the deposition process. The films showed amorphous structures with nanoparticles and a decreased deposition rate with increasing oxygen flow ratio. The conductive mechanism of the films was attributed to the ratio of substitutional Sn atoms and the SnO2 phase. Metal-semiconductor-metal solar-blind photodetectors were developed and analyzed to demonstrate the effect of oxygen flow ratio.
CERAMICS INTERNATIONAL
(2023)
Article
Instruments & Instrumentation
Pai Li, Jiawei Wang, Zhiqiang Li, Ping Zhang, Xin Cao, Jiajun Xu, Jiajun Zheng, Yinmei Lu, Yunbin He
Summary: Co-doping Sn and W into VO2 can enhance its thermochromic properties, making it suitable for smart window applications.
INFRARED PHYSICS & TECHNOLOGY
(2023)
Article
Chemistry, Physical
Keyun Gu, Zilong Zhang, Ke Tang, Jian Huang, Meiyong Liao, Linjun Wang
Summary: This study successfully fabricates high-performance solar-blind UV detectors by depositing amorphous Ga2O3 films and demonstrates their excellent responsivity, external quantum efficiency, detectivity, and rapid photo-response speed. The results provide a promising strategy for the fabrication of high-performance Ga2O3-based solar-blind UV detectors.
APPLIED SURFACE SCIENCE
(2022)
Article
Green & Sustainable Science & Technology
Rosario Vidal, Jaume-Adria Alberola-Borras, Severin N. Habisreutinger, Joaquin-Luis Gimeno-Molina, David T. Moore, Tracy H. Schloemer, Ivan Mora-Sero, Joseph J. Berry, Joseph M. Luther
Summary: The study analyzes the human health toxicity and environmental implications of solvents used in perovskite solar cells, recommending dimethyl sulfoxide (DMSO) as the green choice for large-scale production.
NATURE SUSTAINABILITY
(2021)
Article
Multidisciplinary Sciences
Young-Hoon Kim, Yaxin Zhai, Haipeng Lu, Xin Pan, Chuanxiao Xiao, E. Ashley Gaulding, Steven P. Harvey, Joseph J. Berry, Zeev Valy Vardeny, Joseph M. Luther, Matthew C. Beard
Summary: Traditional optoelectronic approaches rely on both electrical and magnetic fields to control spin, charge, and light, while the use of chiral-induced spin selectivity (CISS) technology allows for the fabrication of a spin-LED that operates at room temperature without the need for magnetic fields or ferromagnetic contacts.
Review
Chemistry, Physical
Eric Amerling, Haipeng Lu, Bryon W. Larson, Annalise E. Maughan, Alan Phillips, Evan Lafalce, Luisa Whittaker-Brooks, Joseph J. Berry, Matthew C. Beard, Z. Valy Vardeny, Jeffrey L. Blackburn
Summary: Research on derivatives of both bulk and low-dimensional metal halide perovskite semiconductors has grown significantly in the past decade, but the understanding and intentional applications of electronic doping have lagged behind. Successful electronic doping of these materials likely requires careful consideration and application of established doping strategies and mechanisms in the semiconductor field.
ACS ENERGY LETTERS
(2021)
Article
Chemistry, Physical
Sarthak Jariwala, Sven Burke, Sean Dunfield, R. Clayton Shallcross, Margherita Taddei, Jian Wang, Giles E. Eperon, Neal R. Armstrong, Joseph J. Berry, David S. Ginger
Summary: By passivating nonradiative defects with APTMS, we controlled surface recombination in mixed-cation, mixed-halide perovskite, achieving high external photoluminescence quantum efficiencies and long minority carrier lifetimes. Our study suggests that surface passivation and contact engineering can enable near-theoretical device efficiencies with these materials, addressing nonradiative loss pathways in mixed-cation mixed-halide films.
CHEMISTRY OF MATERIALS
(2021)
Article
Energy & Fuels
Davide Regaldo, Aleksandra Bojar, Sean P. Dunfield, Pilar Lopez-Varo, Mathieu Fregnaux, Vincent Dufoulon, Shan-Ting Zhang, Jose Alvarez, Joseph J. Berry, Jean-Baptiste Puel, Philip Schulz, Jean-Paul Kleider
Summary: Lead halide perovskites are utilized in semiconductor devices as absorbers with low doping levels to achieve high surface photovoltage values. Drift-diffusion simulations show that under continuous illumination, intrinsic perovskite-SCTL structures can develop mV range surface photovoltages, while actual measurements confirm SPVs in the hundreds of mV. The compatibility between low doping and defect densities in the perovskite layer and high SPV values is analyzed using numerical modeling to understand the electronic processes contributing to long SPV persistence after the illumination is switched off.
PROGRESS IN PHOTOVOLTAICS
(2022)
Article
Chemistry, Physical
Moses Kodur, Zachary Dorfman, Ross A. Kerner, Justin H. Skaggs, Taewoo Kim, Sean P. Dunfield, Axel Palmstrom, Joseph J. Berry, David P. Fenning
Summary: Optimizing selective contact layers in photovoltaics is essential for high-performing stable devices. Using vacuum thermally evaporated tin oxide as a case study demonstrates the effectiveness of simple electrochemical tests in screening device-relevant contact layer properties, aiding in process development and quality control. Fast, reliable, scalable, and actionable probes of electronic properties become increasingly important as halide perovskite photovoltaics approach their theoretical limits and scale to large-area devices.
ACS ENERGY LETTERS
(2022)
Article
Chemistry, Physical
Laura E. Mundt, Fei Zhang, Axel F. Palmstrom, Junwei Xu, Robert Tirawat, Leah L. Kelly, Kevin H. Stone, Kai Zhu, Joseph J. Berry, Michael F. Toney, Laura T. Schelhas
Summary: This study demonstrates the impact of nanoscale compositional heterogeneity on the long-term stability of MHP solar cells using mixed A-site FA(0.83)Cs(0.17)PbI(3), and reveals that thermal annealing conditions during film processing can influence nan-scale compositional heterogeneity, with potential to improve device performance stability.
ACS ENERGY LETTERS
(2022)
Article
Chemistry, Multidisciplinary
Young-Hoon Kim, Ruyi Song, Ji Hao, Yaxin Zhai, Liang Yan, Taylor Moot, Axel F. Palmstrom, Roman Brunecky, Wei You, Joseph J. Berry, Jeffrey L. Blackburn, Matthew C. Beard, Volker Blum, Joseph M. Luther
Summary: This study investigates how chiral ligands attached to perovskite nanocrystal surfaces distort the perovskite lattice and demonstrates the resulting chiral electro-optical properties. The major finding is a centro-asymmetric distortion of the surface lattice, which is likely the cause of the chiral-optical properties. Spin-polarized transport through chiral nanocrystals amplifies the discrimination between left and right-handed circularly polarized light.
ADVANCED FUNCTIONAL MATERIALS
(2022)
Article
Chemistry, Physical
Samuel Berweger, Fei Zhang, Bryon W. Larson, Andrew J. Ferguson, Axel F. Palmstrom, Obadiah G. Reid, Thomas M. Wallis, Kai Zhu, Joseph J. Berry, Pavel Kabos, Sanjini U. Nanayakkara
Summary: The optoelectronic properties of lead halide perovskite thin films can be tuned through compositional variations and strain. However, the nanocrystalline structure complicates the understanding of the link between composition, processing conditions, and material properties. In this study, the local photoconductivity dynamics of perovskite thin films were investigated under different processing conditions and degradation using microwave near-field microscopy. The results showed that the annealing temperature during the processing affected the film morphology, stability, and spatial photoconductivity distribution. Spectral evidence of halide segregation-induced degradation was found in the mixed halide formulation, while an increase in carrier lifetime was observed in the FACs formulation annealed at 180 degrees C.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2022)
Editorial Material
Chemistry, Physical
E. Ashley Gaulding, Amy E. Louks, Mengjin Yang, Robert Tirawat, Mickey J. Wilson, Liam K. Shaw, Timothy J. Silverman, Joseph M. Luther, Axel F. Palmstrom, Joseph J. Berry, Matthew O. Reese
ACS ENERGY LETTERS
(2022)
Article
Chemistry, Physical
Ross A. Kerner, Kelly Schutt, Kai Zhu, Joseph J. Berry
Summary: Non-negligible impurities of acetate and nitrate have been found in commercially available PbI2 reagents, which can accelerate the degradation of mixed-cation halide perovskite inks. Therefore, better control of the purity of halide perovskites is necessary.
ACS ENERGY LETTERS
(2022)
Article
Chemistry, Physical
Ross A. Kerner, Earl D. Christensen, Steven P. Harvey, Jonah Messinger, Severin N. Habisreutinger, Fei Zhang, Giles E. Eperon, Laura T. Schelhas, Kai Zhu, Joseph J. Berry, David T. Moore
Summary: Using higher quality reagents to synthesize halide perovskite materials can improve their optoelectronic performance. In this study, we investigated the influence of different PbI2 reagent sources on device performance and identified acetate and potassium as key impurities affecting performance. A simple aqueous recrystallization method successfully reduced impurity concentration and improved device performance.
ACS APPLIED ENERGY MATERIALS
(2022)
Article
Energy & Fuels
Jackson W. Schall, Andrew Glaws, Nutifafa Y. Doumon, Timothy J. Silverman, Michael Owen-Bellini, Kent Terwilliger, Md Aslam Uddin, Prem Rana, Joseph J. Berry, Jinsong Huang, Laura T. Schelhas, Dana B. Kern
Summary: In this study, electroluminescence (EL) and thermal imaging were used to investigate the degradation of metal halide perovskite (MHP) photovoltaic (PV) mini-modules. Different spatial patterns were observed in the EL images depending on the external stress conditions. Dark speckle features dominated after UV stress, while lateral intensity gradients were prominent after thermal cycling stress. Multimodal electro-optical imaging, including EL, photoluminescence and dark lock-in thermography, provided a deeper understanding of the degradation modes. UV exposure and thermal cycling stress testing alone could not replicate the same degradation signatures observed after outdoor deployment, indicating the occurrence of multiple degradation modes. The spatial characterization of degradation modes provides a foundation for developing targeted accelerated stress testing procedures by comparing with outdoor aging.
Article
Multidisciplinary Sciences
Qi Jiang, Robert Tirawat, Ross A. Kerner, E. Ashley Gaulding, Yeming Xian, Xiaoming Wang, Jimmy M. Newkirk, Yanfa Yan, Joseph J. Berry, Kai Zhu
Summary: Metal halide perovskite solar cells (PSCs) show great potential as a low-cost thin-film photovoltaic technology. To ensure their commercialization, it is important to understand their reliability under real-world outdoor conditions. This study demonstrates that indoor accelerated stability tests can predict the performance of PSCs in outdoor environments. The degradation rates under illumination and elevated temperatures are found to be the most informative for assessing device reliability. The study also identifies the interface between indium tin oxide/self-assembled monolayer-based hole transport layer and perovskite layer as a key factor affecting device stability.
Article
Materials Science, Multidisciplinary
Jinhui Tong, Jue Gong, Mingyu Hu, Srinivas K. Yadavalli, Zhenghong Dai, Fei Zhang, Chuanxiao Xiao, Ji Hao, Mengjin Yang, Michael A. Anderson, Erin L. Ratcliff, Joseph J. Berry, Nitin P. Padture, Yuanyuan Zhou, Kai Zhu
Summary: The study demonstrates high efficiency and stability of tin-lead based perovskite solar cells with an ideal band gap, achieved through the use of a specific complex additive to improve microstructure and reduce residual stress, enhancing the efficiency and stability of the ideal-band-gap PSCs.