Article
Chemistry, Physical
Pamela Machado, Roger Guzman, Ramon J. . Morera, Jordi Alcala, Anna Palau, Wu Zhou, Mariona Coll
Summary: The need for highly performant and stable p-type transparent electrodes based on abundant metals is driving research on perovskite oxide thin films. Cost-efficient and scalable solution-based techniques are being explored to prepare these materials and extract their full potential.
CHEMISTRY OF MATERIALS
(2023)
Article
Materials Science, Multidisciplinary
Michael Seifert, Moemi Kawashima, Claudia Roedl, Silvana Botti
Summary: Zinc blende copper iodide, a p-type semiconductor transparent in the visible range, has potential for transparent electronics, with the layered beta-phase being suitable for 2D applications. Both phases exhibit small light-hole effective masses and large band gaps, characteristics that are also present in the beta-CuI monolayer, indicating the potential for a high-performance transparent monolayer conductor for 2D electronics.
JOURNAL OF MATERIALS CHEMISTRY C
(2021)
Article
Chemistry, Multidisciplinary
Owen Kendall, Lesly Melendez, Jiawen Ren, Samantha Prabath Ratnayake, Billy J. Murdoch, Edwin L. H. Mayes, Joel van Embden, Daniel E. Gomez, Arrigo Calzolari, Enrico Della Gaspera
Summary: In this study, spinel copper gallate (CuGa2O4) nanocrystals with an average size of 3.7 nm were synthesized and characterized via a heat-up colloidal reaction. The CuGa2O4 nanocrystals have a band gap of -2.5 eV and exhibit p-type character, which is consistent with ab initio simulations. When deposited as thin films, these novel nanocrystals are shown to be photoactive, generating a clear and reproducible photocurrent under blue light irradiation. The ability to adjust the Cu/Ga ratio within the nanocrystals and its effect on their optical and electronic properties was also demonstrated. These findings position CuGa2O4 nanocrystals as a promising material for optoelectronic applications, including hole transport and light harvesting.
Article
Chemistry, Physical
Kyunghan Ahn, Ga Hye Kim, Se-Jun Kim, Jihyun Kim, Gi-Seong Ryu, Paul Lee, Byungki Ryu, Jung Young Cho, Yong-Hoon Kim, Joohoon Kang, Hyungjun Kim, Yong-Young Noh, Myung-Gil Kim
Summary: This study reports the synthesis of highly conductive transparent p-type sulfur-doped CuI (CuI:S) thin film using a liquid-iodination method with a thiol additive. The CuI:S film exhibits a remarkably high electrical conductivity and optical transmittance, achieving a record-high figure of merit (FOM) value. The CuI:S electrode is successfully utilized in transparent electronic devices.
CHEMISTRY OF MATERIALS
(2022)
Article
Materials Science, Multidisciplinary
Ruibin Xue, Gang Gao, Lei Yang, Liangge Xu, Yumin Zhang, Jiaqi Zhu
Summary: In this study, composite films of CuI-Cu2O were successfully developed, with improved surface morphology and electronic properties. The optimized CuI-Cu2O films demonstrated good transparency, low hole concentration, high hole mobility, and high conductivity. Additionally, the electrical properties of CuI-Cu2O films exhibited greater stability compared to pure CuI films.
JOURNAL OF MATERIALS CHEMISTRY C
(2023)
Article
Materials Science, Multidisciplinary
Mi Zhong, Wei Zeng, Fu-Sheng Liu, Dai-He Fan, Bin Tang, Qi-Jun Liu
Summary: A screening strategy was formulated to identify promising p-type transparent conducting materials, resulting in the identification of three candidates with excellent properties. Defect calculations provided strong support for the established criterion for assessing p-type performance, indicating potential for further exploration and design of advanced functional materials.
MATERIALS TODAY PHYSICS
(2022)
Article
Materials Science, Multidisciplinary
Moufdi Hadjab, Olga Guskova, Hamza Bennacer, Mohamed Issam Ziane, Abderrahim Hadj Larbi, M. A. Saeed
Summary: In this study, the physical ground-state properties of three novel semiconductors were investigated using Density Functional Theory (DFT) and various computational methods. The study focused on the optical, structural, and electronic properties of CuMO2 (M= Al, Sc, and Y) transparent conducting oxides. The results were compared to previous theoretical and experimental studies, and it was found that these ternary delafossite compounds have potential as alternative materials in photovoltaic applications.
MATERIALS TODAY COMMUNICATIONS
(2022)
Article
Chemistry, Physical
Ying Wang, Chung Yan Lo, Yeung Sum Wong, Cheuk Kai Gary Kwok, Sujit Kumer Shil, Kin Man Yu
Summary: The study synthesized a new class of amorphous ionic oxide semiconductors (AIOSs) CdO-Ga2O3 alloys, exhibiting high electron mobility and low resistivity suitable for flexible electronic applications. Amorphous Cd1-xGaxO1+delta alloy films show higher resistance to repeated compressive bending compared to crystalline films, while crystalline films show less electrical degradation after repeated tensile bending.
JOURNAL OF ALLOYS AND COMPOUNDS
(2021)
Review
Chemistry, Multidisciplinary
Ao Liu, Huihui Zhu, Myung-Gil Kim, Junghwan Kim, Yong-Young Noh
Summary: This paper discusses the potential of CuI as a promising p-type material in various devices, including transparent electrodes, thermoelectric devices, p-n diodes, transistors, light emitting diodes, and solar cells. The focus is on the electronic structure and defect states of CuI, as well as the design concepts for adjusting its optoelectrical properties through different approaches.
Article
Chemistry, Inorganic & Nuclear
Han Gao, Xianwei Zeng, Qiang Guo, Zhi Yang, Yanwen Deng, Hong Li, Dehua Xiong
Summary: In this study, Ca doped CuScO2 delafossite oxides were synthesized using the hydrothermal method, with increasing Ca dopant leading to thinner sheets and decreased conductivity. Additionally, all samples exhibited absorption in the visible light region, and the optical band gap values showed a blue shift with increasing Ca dopant. These results suggest potential applications of these materials in optoelectronic devices.
DALTON TRANSACTIONS
(2021)
Article
Chemistry, Multidisciplinary
Mahdad Mohammadi, Ruiwen Xie, Niloofar Hadaeghi, Aldin Radetinac, Alexey Arzumanov, Philipp Komissinskiy, Hongbin Zhang, Lambert Alff
Summary: This study demonstrates that the absorption and reflection edges of SrV1-xMoxO3 solid solution can be shifted to the edges of the visible light spectrum, making it a potential alternative to indium tin oxide (ITO) with extremely low sheet resistance. The optimum composition with x = 0.5 shows a resistivity of 32 mu omega cm and transmittance above 84% across the visible spectrum. The shift of the plasma frequency is governed by the interplay of d-band filling and electronic correlations. This research contributes to the understanding of highly conducting perovskites for sustainable transparent conductors and emergent plasmonics.
ADVANCED MATERIALS
(2023)
Article
Materials Science, Multidisciplinary
Mohamed Salah, Joonseok Yoon, Mohamed M. El-Desoky, Zahid Hussain, Honglyoul Ju, Sung-Kwan Mo
Summary: Copper-based delafossite oxides are excellent candidates for p-type transparent conducting oxide in transparent semiconductor applications. We reported the low-energy electronic structure of CuAlO2 using angle-resolved photoemission spectroscopy (ARPES), and found important characteristics such as hole bands and effective masses.
CURRENT APPLIED PHYSICS
(2022)
Article
Engineering, Electrical & Electronic
Dan Yang, Yongqing Huang, Kai Liu, Xiaofeng Duan, Yisu Yang, Xiaomin Ren
Summary: The NiO thin film has exhibited ohmic contact with both p-type and non-doped InGaAs, mainly due to the small valence band offset between NiO and InGaAs. The oxidation time is a key factor affecting the contact properties of NiO/InGaAs. The application of NiO transparent electrodes in III-V compound material-based optical-electronic devices shows great promise.
MATERIALS SCIENCE IN SEMICONDUCTOR PROCESSING
(2021)
Article
Materials Science, Ceramics
Akane Samizo, Makoto Minohara, Naoto Kikuchi, Kenta Ando, Yuta Mazuka, Keishi Nishio
Summary: The study investigated the impact of Nb/Ta ratio on hole-generation efficiency in Sn2Nb2-xTaxO7 with pyrochlore structure, revealing the critical role of the B-site element in suppressing defects and disorder in the Sn4O tetrahedra and thus improving hole-carrier-generation efficiency.
JOURNAL OF THE AMERICAN CERAMIC SOCIETY
(2023)
Article
Materials Science, Multidisciplinary
Chenhui Li, Penglai Gong, Jinxing Zheng, Minglin Zhao, Renhuai Wei, Wangping Cheng, Ling Hu, Wenhai Song, Xuebin Zhu, Yuping Sun
Summary: Researchers have successfully designed and fabricated a high-performance p-type 4d transition metal Rh-based CuRhO2 film using a facile solution method, achieving high room-temperature conductivity of 735 S cm(-1) through the substitution of 10%Mg in Rh sites. Additionally, the acceptor-doped CuRhO2 films exhibit high near-infrared transmittance and low room-temperature sheet resistance. The electronic structure, electrical transport mechanism, and intra-band excitation feature of the CuRhO2 film have also been unveiled, making a significant advancement in p-type TC films.
ADVANCED OPTICAL MATERIALS
(2022)
Article
Materials Science, Multidisciplinary
Alexandra Papadogianni, Charlotte Wouters, Robert Schewski, Johannes Feldl, Jonas Lahnemann, Takahiro Nagata, Elias Kluth, Martin Feneberg, Rudiger Goldhahn, Manfred Ramsteiner, Martin Albrecht, Oliver Bierwagen
Summary: In this study, single-crystalline bixbyite (In1-xGax)(2)O-3 films were grown on (111)-oriented yttria-stabilized zirconia substrates using plasma-assisted molecular beam epitaxy. The addition of a pure In2O3 buffer layer between the substrate and (In1-xGax)(2)O-3 alloy improved the film surface smoothness and crystallinity. The distribution of Ga cations in the films was found to be non-uniform, with high Ga density inclusions observed at higher Ga content. The cubic bixbyite phase was preserved in both the matrix and the inclusions.
PHYSICAL REVIEW MATERIALS
(2022)
Article
Nanoscience & Nanotechnology
Venkateshkumar Prabhakaran, Garvit Agarwal, Jason D. Howard, Sungun Wi, Vaithiyalingam Shutthanandan, Dan-Thien Nguyen, Luke Soule, Grant E. Johnson, Yi-Sheng Liu, Feipeng Yang, Xuefei Feng, Jinghua Guo, Kie Hankins, Larry A. Curtiss, Karl T. Mueller, Rajeev S. Assary, Vijayakumar Murugesan
Summary: Charge transfer across the electrode-electrolyte interface is studied using ion soft landing method to prepare well-defined interfaces with molecular precision. In situ multimodal spectroscopic characterization is used to investigate the reactivity of solvated species in Mg batteries. Computed reaction pathways and energy barriers are used to confirm the experimental results. The TFSI reactivity is evaluated under electrochemical conditions using phase-separated electrolytes.
ACS APPLIED MATERIALS & INTERFACES
(2023)
Article
Chemistry, Multidisciplinary
Piero Mazzolini, Zsolt Fogarassy, Antonella Parisini, Francesco Mezzadri, David Diercks, Matteo Bosi, Luca Seravalli, Anna Sacchi, Giulia Spaggiari, Danilo Bersani, Oliver Bierwagen, Benjamin Moritz Janzen, Marcella Naomi Marggraf, Markus R. Wagner, Ildiko Cora, Bela Pecz, Abbes Tahraoui, Alessio Bosio, Carmine Borelli, Stefano Leone, Roberto Fornari
Summary: Unintentionally doped kappa-Ga2O3 epitaxial films on sapphire substrates exhibit columnar rotational domains that inhibit in-plane electronic conduction. The introduction of silane doping increases the domain size and mobility, improving in-plane conduction. Non-destructive techniques based on X-ray diffraction and Raman spectroscopy can be used to compare domain dimensions.
ADVANCED FUNCTIONAL MATERIALS
(2023)
Article
Physics, Applied
Kingsley Egbo, Esperanza Luna, Jonas Laehnemann, Georg Hoffmann, Achim Trampert, Jona Gruembel, Elias Kluth, Martin Feneberg, Ruediger Goldhahn, Oliver Bierwagen
Summary: By combining SnO2 and Sn, we successfully grew phase-pure single-crystalline metastable SnO (001) thin films on Y-stabilized ZrO2 (001) substrates using suboxide molecular beam epitaxy (S-MBE) at a growth rate of about 1.0 nm/min without additional oxygen. These films exhibit epitaxial growth over a wide temperature range of 150 to 450°C. The obtained p-type SnO films at low substrate temperatures show promise for back-end-of-line (BEOL) compatible applications and integration with n-type oxides in pn heterojunctions and field-effect transistors.
JOURNAL OF APPLIED PHYSICS
(2023)
Article
Nanoscience & Nanotechnology
Navid Attarzadeh, Debabrata Das, Srija N. Chintalapalle, Susheng Tan, V. Shutthanandan, C. V. Ramana
Summary: In this study, a highly efficient heterostructure catalyst for hydrogen production was designed using a 3D nano architecture inspired by the prickly pear cactus. The catalyst exhibited superior catalytic activity and stability compared to conventional catalysts. The introduction of heterointerfaces and epitaxial NiS nanosheets expanded the active catalytic surface area and enhanced the intrinsic catalytic activity.
ACS APPLIED MATERIALS & INTERFACES
(2023)
Article
Physics, Applied
Zhenni Yang, Xiangyu Xu, Yan Wang, Siliang Kuang, Duanyang Chen, Hongji Qi, K. H. L. Zhang
Summary: Si-doped beta-Ga2O3 thin films grown on vicinal a-Al2O3 (0001) substrates exhibit high electrical conductivity and deep ultraviolet (DUV) transparency, making them promising candidates for transparent electrodes. The use of miscut Al2O3 substrates promotes improved crystal quality and electrical properties. The Si-doped films achieved a high conductivity of 37 S cm(-1) and average DUV transparency of 85% on a 6 degrees miscut substrate. The films also exhibit low work function, making them suitable for efficient electron injection in DUV optoelectronic devices.
APPLIED PHYSICS LETTERS
(2023)
Article
Physics, Applied
Kingsley Egbo, Jonas Laehnemann, Andreas Falkenstein, Joel Varley, Oliver Bierwagen
Summary: (La and Ga)-doped tin monoxide thin films were grown with dopant concentrations ranging from approximate to 5 x 10(18) to 2 x 10(21) cm(-3). Ga acted as an acceptor and La as a compensating donor in the doped samples. The results show the possibilities of controlling the hole concentration in p-type SnO, which can be useful for a range of optoelectronic and gas-sensing applications.
APPLIED PHYSICS LETTERS
(2023)
Article
Chemistry, Physical
Henry W. Sprueill, Jenna A. Bilbrey, Qin Pang, Peter V. Sushko
Summary: Neural network potentials (NNPs) can accelerate atomistic simulations and allow broader sampling of structural outcomes and transformation pathways. In this study, an active sampling algorithm is demonstrated to train an accurate NNP for microstructural evolutions. The NNP is then used with a perturbation scheme to stochastically sample structural and energetic changes caused by shear-induced deformation, revealing a range of possible intermixing and vacancy migration pathways. The code for the active learning strategy and NNP-driven shear simulations is openly available.
JOURNAL OF CHEMICAL PHYSICS
(2023)
Article
Physics, Condensed Matter
Anna Reis, Michael Hanke, Oliver Bierwagen, Achim Trampert, Piero Mazzolini, Edmund Welter
Summary: The local ordering in amorphous Ga2O3 and (InxGa1-x)(2)O-3 thin films on Si(111) and its change on crystallization upon annealing were investigated. The bonding character of the Ga cations was studied using synchrotron-based extended X-ray absorption fine structure data and a numerical implementation of the scattering process. The results showed the preferential formation of GaO4 tetrahedrons in the amorphous films, while annealing led to the formation of monoclinic beta-Ga2O3 crystallites with both tetra- and octahedral coordination for the amorphous Ga2O3 film.
PHYSICA STATUS SOLIDI B-BASIC SOLID STATE PHYSICS
(2023)
Article
Materials Science, Multidisciplinary
Minghang Li, Wencheng Chen, Jiasheng Zhang, Shuming Bai, Jiarong Zeng, Xueliang Zhu, Kelvin H. L. Zhang, Qijin Cheng, Kostya (Ken) Ostrikov
Summary: AlN is commonly used as a buffer layer in GaN-based LEDs, but when applied on patterned sapphire substrate (PSS), it leads to undesired screw dislocations in the epitaxial layer of GaN. This study demonstrates the use of sputtered AlON buffer layer on industry-grade four-inch PSS to improve the quality of GaN epitaxial layers and enhance the performance of GaN-based blue LEDs. The addition of oxygen to AlN reduces the density of screw dislocations, providing insights into the growth mechanisms and guiding the development of next-generation optoelectronic technologies.
PHYSICA STATUS SOLIDI-RAPID RESEARCH LETTERS
(2023)
Article
Chemistry, Multidisciplinary
Rongbin Wang, Thorsten Schultz, Alexandra Papadogianni, Elena Longhi, Christos Gatsios, Fengshuo Zu, Tianshu Zhai, Stephen Barlow, Seth R. Marder, Oliver Bierwagen, Patrick Amsalem, Norbert Koch
Summary: In2O3, a transparent transition metal oxide, can have an enhanced or depleted surface electron accumulation layer (SEAL) depending on the density of oxygen vacancies at the surface. By adsorbing molecular electron donors or acceptors, the SEAL of In2O3 can be tuned. This work demonstrates that adsorption of [RuCp*mes](2) restores the SEAL, while adsorption of F(6)TCNNQ depletes the SEAL and generates upward band bending at the In2O3 surface.
Article
Chemistry, Multidisciplinary
Guangdong Liu, Yang He, Zhixiao Liu, Hui Wan, Yaobin Xu, Huiqiu Deng, Hui Yang, Ji-Guang Zhang, Peter V. V. Sushko, Fei Gao, Chongmin Wang, Yingge Du
Summary: By using in situ transmission electron microscopy and density functional theory calculations, the influence of planar defects on the diffusion pathways and transport kinetics of Li ions in a tungsten trioxide lattice is revealed. It is found that planar defects disrupt the continuity of ion conduction channels by altering the charge distribution and lattice spacing, leading to a significant increase in energy barrier for Li diffusion. This atomic-level understanding has important implications for rational interface design in solid-state batteries and solid oxide fuel cells.
Article
Materials Science, Multidisciplinary
Matthew Chrysler, Judith Gabel, Tien-Lin Lee, Zihua Zhu, Tiffany C. Kaspar, Mark Bowden, Peter V. Sushko, Scott A. Chambers, Joseph H. Ngai
Summary: Charge redistribution across heterojunctions influences the functionality of materials systems. The composition of the terminating surface affects charge transfer across a Si/SrTiO3 heterojunction. Surface depletion in Si causes itinerant electrons to migrate across the interface and modify the interfacial dipole. This leads to a change in band alignment, which can be weakened by capping the SrTiO3 surface.
PHYSICAL REVIEW MATERIALS
(2023)
Article
Chemistry, Multidisciplinary
Yan Sun, Cheng-Rong Wu, Tian-Yi Ding, Jian Gu, Jia-Wei Yan, Jun Cheng, Kelvin H. L. Zhang
Summary: Researchers used electrochemical-scanning tunnelling microscopy (EC-STM) to directly observe the structural dynamics of LaNiO3 (LNO) surface during the oxygen-evolution reaction (OER). They discovered that the reconstruction of surface morphology originated from the transition of Ni species on the LNO surface. The change in surface topography was induced by the Ni(OH)(2)/NiOOH redox transformation. These findings demonstrate the importance of in situ characterization for understanding the dynamic nature of catalyst interfaces and designing efficient electrocatalysts.
Article
Multidisciplinary Sciences
Prescott E. Evans, Yang Wang, Peter V. Sushko, Zdenek Dohnalek
Summary: This study investigates the deposition of palladium (Pd) on WTe2(001) and finds that Pd nucleation is driven by the interaction with excess tellurium (Te) atoms. The formation of Pd-Te clusters is not affected by surface defects and remains stable at elevated temperatures. These findings are important for the manufacturing of novel quantum and microelectronics devices and catalytically active nano-alloy centers.
