Article
Nanoscience & Nanotechnology
Jack E. N. Swallow, Robert G. Palgrave, Philip A. E. Murgatroyd, Anna Regoutz, Michael Lorenz, Anna Hassa, Marius Grundmann, Holger von Wenckstern, Joel B. Varley, Tim D. Veal
Summary: The study investigates the electronic and optical properties of (InxGa1-x)(2)O-3 alloys with a lateral cation composition gradient and three crystallographic phases. It reveals the optical gaps and surface space-charge properties, as well as the electronic structure of different phases. The properties of the alloys, such as n-type dopability of In2O3 and the use of Ga2O3 as a solar-blind UV detector, are understood in comparison to other common-cation compound semiconductors based on simple chemical trends of band edge positions and volume deformation potential.
ACS APPLIED MATERIALS & INTERFACES
(2021)
Article
Materials Science, Multidisciplinary
Hussein O. Badr, Francisco Lagunas, Daniel E. Autrey, Jacob Cope, Takayuki Kono, Takeshi Torita, Robert F. Klie, Yong-Jie Hu, Michel W. Barsoum
Summary: We synthesized 1D TiO2-based nanofilaments by reacting Ti-containing precursors with quaternary ammonium hydroxides at near-ambient conditions. The structure was previously believed to be anatase-based, but we now conclude that it is actually a 1D titania lepidocrocite-based structure. The NFs grow along [100] and tend to self-assemble/stack in two directions. The band gap is not affected by the nature of the cations surrounding the NFs.
Article
Chemistry, Physical
Gergely Tarsoly, Jae-Yun Lee, Fei Shan, Sung-Jin Kim
Summary: This paper presents a resistive memory based on TiO2 and a-IGZO thin films with optimized annealing temperature. The study proposes a memory mechanism and demonstrates low voltage operation, good retention stability, and endurance stability of the device.
APPLIED SURFACE SCIENCE
(2022)
Article
Materials Science, Multidisciplinary
Sabrina Selva, Quentin Bignon, Amandine Raynal, Frantz Martin, Quentin Auzoux, Gilles Renou, Michel Tabarant, Frederic Miserque, Laurence Latu-Romain, Yves Wouters
Summary: The corrosion of titanium alloys in primary water at 300 degrees Celsius resulted in a global weight gain due to oxidation and surface precipitation, with a protective ilmenite layer finally precipitating at the surface of the samples.
Article
Engineering, Chemical
Jacek Fal, Jolanta Sobczak, Ryszard Stagraczynski, Patrice Estelle, Gawel Zyla
Summary: The electrical conductivity of ethylene glycol-based nanofluids containing three types of titanium dioxide nanoparticles was investigated experimentally, and a new theoretical correlation was proposed. The influence of nanoparticle content and phase on the electrical conductivity of ethylene glycol was observed.
Review
Chemistry, Multidisciplinary
Diana Rakhmawaty Eddy, Muhamad Diki Permana, Lintang Kumoro Sakti, Geometry Amal Nur Sheha, Solihudin, Sahrul Hidayat, Takahiro Takei, Nobuhiro Kumada, Iman Rahayu
Summary: This study aims to clarify the differences between titanium dioxide polymorphs and their properties in different photocatalytic applications. Homophase titanium dioxide has disadvantages such as high recombination rates and low adsorption capacity. On the other hand, heterophase titanium dioxide can effectively stimulate electron transfer and exhibit superior photocatalytic performance. Various biphase and triphase polymorphs of titanium dioxide are discussed, and the focus is on the synthesis and application of heterophase titanium dioxide as a photocatalyst.
Article
Chemistry, Multidisciplinary
Anna Yu Kurenkova, Anastasiya Yu Yakovleva, Andrey A. Saraev, Evgeny Yu Gerasimov, Ekaterina A. Kozlova, Vasily V. Kaichev
Summary: This study proposes titania-based photocatalysts modified with copper compounds for hydrogen evolution and tests their photocatalytic activity. The synthesized photocatalysts are characterized using various methods, and the results show that the heat-treated and copper oxide deposited photocatalysts exhibit high activity under both UV and visible light irradiation.
Article
Materials Science, Multidisciplinary
Federica Ceriani, Luca Casanova, Luca Massimini, Andrea Brenna, Marco Ormellese
Summary: This research investigates the influence of two types of particles on the properties of PEO coatings on titanium. The study finds that coatings produced at a specific electrical condition exhibit a thicker and more corrosion-resistant layer, while other treatments affect the structure and performance of the coatings.
Article
Environmental Sciences
Sunil Babu Eadi, Han Yan, P. Senthil Kumar, Yuvakkumar Rathinam, Hi-Deok Lee
Summary: In this study, the performance of IGZO-decorated ZnO films for the detection of NO2 gas was investigated by changing the IGZO deposition time. The results showed that decorating ZnO with IGZO can significantly increase the sensor response.
ENVIRONMENTAL RESEARCH
(2022)
Article
Nanoscience & Nanotechnology
Kasidid Yaemsunthorn, Marcin Kobielusz, Wojciech Macyk
Summary: The low-temperature synthesis of TiO2 nanocomposites allows precise tuning of the anatase/rutile ratio. Different phase compositions have varying impacts on water oxidation, hydrogen peroxide reduction, and water reduction reactions, with the A series showing higher activity in oxidation-controlled reactions and the B series facilitating reduction-controlled processes. The design of optimal photocatalysts should consider both intrinsic and extrinsic factors for improved catalytic activity.
ACS APPLIED NANO MATERIALS
(2021)
Article
Anatomy & Morphology
Muhammad Hafeez, Wajid Shamim, Rimsha Ehsan, Zain-ul Abdin, Salah Ud Din, Sirajul Haq, Abdulhameed Khan, Shabnam Shahida, Usman Hameed
Summary: This study synthesized titanium dioxide nanoparticles using Cannabis sativa leaves extract and found that the nanoparticles exhibit higher antimicrobial activity against Gram-negative bacteria compared to Gram-positive bacteria, indicating a potential new approach to combat antimicrobial drug resistance.
MICROSCOPY RESEARCH AND TECHNIQUE
(2021)
Article
Optics
V. S. Krivobok, S. N. Nikolaev, D. A. Zazymkina, D. F. Aminev, S. I. Chentsov, I. I. Minaev, E. E. Onishchenko, M. A. Chernopitssky, A. A. Narits
Summary: This paper discusses the near-IR luminescence characteristics of crystalline titanium dioxide powders with different particle sizes. The luminescence system is governed by inner shells of transition elements located in the rutile lattice.
JOURNAL OF LUMINESCENCE
(2022)
Article
Physics, Applied
Elias Kluth, Michael Fay, Christopher Parmenter, Joseph Roberts, Emily Smith, Craig Stoppiello, Fabien Massabuau, Ruediger Goldhahn, Martin Feneberg
Summary: This study investigates the redshift of the absorption onset and amplitude increase in the ultraviolet complex dielectric function (DF) of corundum-like a-(TixGa1-x)(2)O-3 with increasing Ti content. a-Ga2O3 thin film samples alloyed with Ti up to x = 0.61 are grown using plasma enhanced atomic layer deposition, and characterized using ultraviolet spectroscopic ellipsometry, transmission electron microscopy, and x-ray photoelectron spectroscopy (XPS). The results show that the samples remain crystalline up to x = 0.053. Ellipsometry reveals a strong red shift in the absorption onset and an increase in amplitude with increasing Ti content, attributed to the successive occupation of Ti-related 3d states in the density-of-states. Valence band XPS results suggest that the red shift is mainly due to conduction band lowering rather than the valence band.
APPLIED PHYSICS LETTERS
(2023)
Article
Chemistry, Multidisciplinary
Ghulam Asghar, Xue Dong, Sudong Chae, Shahid Saqlain, Seungbae Oh, Kyung Hwan Choi, Jiho Jeon, Chaeheon Woo, Tae Yeong Kim, Jungyoon Ahn, Hyung-Suk Oh, Jae-Hyuk Park, Hak Ki Yu, Jae-Young Choi
Summary: Ultraviolet radiation poses serious health risks, leading to an urgent need for more effective and safer UV filters. In this study, titanium dioxide nanoparticles were successfully embedded in silica microspheres, resulting in a new material with excellent UV protection abilities.
CRYSTAL GROWTH & DESIGN
(2022)
Article
Materials Science, Ceramics
Aleksandr Sivkov, Yuliya Vympina, Alexander Ivashutenko, Iliyas Rakhmatullin, Yuliya Shanenkova, Dmitriy Nikitin, Ivan Shanenkov
Summary: This study proposes a method to obtain highly defect structures of titanium dioxide through a high-energy plasma dynamic synthesis method. By optimizing the synthesis conditions, including the process energy and parameters of the gaseous medium, titanium dioxide powders with a tunable ratio of rutile and anatase modifications and a particle size distribution were synthesized. The resulting titanium dioxide powder has a reduced band gap and an extended working absorption spectrum region. The possibility of photocatalytic applications for the synthesized powder was demonstrated.
CERAMICS INTERNATIONAL
(2022)
Article
Physics, Applied
Md Minhazul Islam, Naresh Adhikari, Armando Hernandez, Adam Janover, Steven Novak, Sahil Agarwal, Charles L. Codding, Michael Snure, Mengbing Huang, Farida A. Selim
JOURNAL OF APPLIED PHYSICS
(2020)
Article
Physics, Applied
J. Anders, M. Kazimierczuk, K. D. Leedy, N. Miller, T. Cooper, M. Streby, M. Schuette
APPLIED PHYSICS LETTERS
(2020)
Article
Physics, Applied
David C. Look, Kevin D. Leedy, Ray-Hua Horng, Marco D. Santia, Stefan C. Badescu
APPLIED PHYSICS LETTERS
(2020)
Article
Engineering, Electrical & Electronic
Neil A. Moser, Tadj Asel, Kyle J. Liddy, Miles Lindquist, Nicholas C. Miller, Shin Mou, Adam Neal, Dennis E. Walker, Steve Tetlak, Kevin D. Leedy, Gregg H. Jessen, Andrew J. Green, Kelson D. Chabak
IEEE ELECTRON DEVICE LETTERS
(2020)
Article
Materials Science, Ceramics
Bingheng Sun, Le Zhang, Guocan Huang, Yanbin Li, Tianyuan Zhou, Jian Kang, Lei Zhang, Yuelong Ma, Qing Yao, Farida A. Selim, Hao Chen
Summary: This study demonstrates the fabrication of high quality YAG:Ce ceramic using LPIM and vacuum sintering methods, achieving high luminous efficiency for LED lighting. By constructing a unique blue chip array, a 4π white light emission with high efficiency is achieved.
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
(2021)
Article
Materials Science, Ceramics
Yuelong Ma, Le Zhang, Tianyuan Zhou, Bingheng Sun, Chen Hou, Shunshun Yang, Jin Huang, Rui Wang, Farida A. Selim, Zhongying Wang, Ming Li, Hao Chen, Yun Wang
Summary: In this study, strategies of controlling crystal-field splitting and ion doping were adopted to fabricate Ce:(Y,Tb)(3)(Al,Mn)(5)O-12 transparent ceramics with high thermal stability and excellent chromaticity parameters. The synergistic effects of Tb3+ and Mn2+ ions significantly improved the color rendering index and achieved a warm white light with low correlated color temperature. The action mechanism of Tb3+ ion and energy transfer between Ce3+ and Mn2+ ions in prepared TCs were verified.
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
(2021)
Article
Physics, Applied
M. Haseman, C. B. Somodi, P. Stepanov, D. E. Wall, L. A. Boatner, P. Hosemann, Y. Q. Wang, B. P. Uberuaga, F. A. Selim
Summary: This study investigates the effects of neutron irradiation on the formation of defects, and on the structural, optical, and electrical properties of ZnO single crystals. The research demonstrates that neutron irradiation leads to significant deterioration of the ZnO structure, forming a high concentration of point defects, vacancy clusters, and voids with large disparities in their structures across different irradiation times. Additionally, neutron irradiation induces significant changes in the optical properties and sample color, as well as the production of new impurities and dopants such as Cu acceptors and Ga donors.
JOURNAL OF APPLIED PHYSICS
(2021)
Article
Physics, Applied
M. M. Islam, M. Bakr, J. N. Aboa, F. A. Selim
Summary: Electron/hole traps play a crucial role in altering the properties of materials, and understanding their dynamics is essential in controlling optoelectronic properties. A highly sensitive thermally stimulated emission spectrometer was developed for detecting shallow traps in bandgap materials, providing a powerful tool for semiconductor research. The technique was successfully tested on Ce doped Y3Al5O12 and Ga2O3, demonstrating its capability for advanced material characterization and exciton dynamics study.
JOURNAL OF APPLIED PHYSICS
(2021)
Article
Materials Science, Multidisciplinary
P. Hosemann, R. Auguste, S. Lam, M. Butterling, M. O. Liedke, A. G. Attallah, E. Hirschmann, A. Wagner, C. P. Grigoropoulos, F. Selim, B. P. Uberuaga
Summary: The study investigates the damage effects of materials treated with short, pulsed lasers using Doppler broadening and positron lifetime annihilation spectroscopy. Clusters of vacancy-like defects and small voids systematically increase with laser power in silicon single crystals, while the damage induced by the laser can reach micrometer depths.
Article
Nanoscience & Nanotechnology
Hyung Min Jeon, Kevin D. Leedy, David C. Look, Celesta S. Chang, David A. Muller, Stefan C. Badescu, Vladimir Vasilyev, Jeff L. Brown, Andrew J. Green, Kelson D. Chabak
Summary: This study successfully synthesized conductive Si-doped beta-Ga2O3 homoepitaxial films with high transparency and promising applications using pulsed laser deposition.
Article
Engineering, Electrical & Electronic
Abhijeet Barua, Ryan J. White, Kevin D. Leedy, Vidya Chidambaran, Rashmi Jha
Summary: Limited work has been done on the behavior of Schottky barrier field-effect transistors for neurotransmitter sensing applications. In this study, low-power deep subthreshold characteristics of thin film transistors made of InGaZnO4 were investigated for the sensitive and selective ex vivo detection of Dopamine. The devices showed promising detection metrics, including a low limit of detection, high binding affinity, and high sensitivity. Furthermore, the devices remained functional even after a regeneration test period, showcasing their potential for long-term use as biosensors.
IEEE SENSORS JOURNAL
(2022)
Article
Physics, Applied
Daram N. Ramdin, Micah S. Haseman, Hsien-Lien Huang, Kevin D. Leedy, Jinwoo Hwang, Leonard J. Brillson
Summary: Iridium is a common impurity in the edge-defined film-fed growth method for producing high-power Ga2O3 device structures, but its effects on carrier transport and recombination have not been fully explored. After nitrogen rapid thermal annealing, the optical and electronic nature of iridium in Ga2O3 and at Ir/Ga2O3 interfaces change on a near-nanometer to micrometer scale, influencing defect-assisted tunneling, diode rectification, and electric field strength preservation. Various measurement techniques reveal the diffusion and impact of iridium in crystal growth, providing insights for improving device performance.
JOURNAL OF APPLIED PHYSICS
(2022)
Review
Materials Science, Multidisciplinary
Farida A. Selim
Summary: Thermoluminescence (TL) spectroscopy measures the positions of localized states/traps in the bandgap by releasing charge carriers using thermal energy. Despite limited applications in semiconductors, recent advances in cryogenic thermally stimulated photoemission spectroscopy (C-TSPS) extend TL measurements to cryogenic temperatures and allow detection of low concentrations of localized states. This article introduces TL and C-TSPS in semiconductor characterization, highlighting their use in measuring ionization energies and characterizing defects. Potential applications in areas such as corrosion and oxide layer formation on metal surfaces are also discussed.
PHYSICA STATUS SOLIDI A-APPLICATIONS AND MATERIALS SCIENCE
(2023)
Article
Chemistry, Physical
P. S. Stepanov, F. A. Selim, S. V. Stepanov, A. V. Bokov, O. V. Ilyukhina, G. Duplatre, V. M. Byakov
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2020)
Article
Materials Science, Multidisciplinary
Yuelong Ma, Le Zhang, Tianyuan Zhou, Bingheng Sun, Yun Wang, Jian Kang, Pan Gao, Jin Huang, Farida A. Selim, Chingping Wong, Ming Li, Hao Chen
JOURNAL OF MATERIALS CHEMISTRY C
(2020)