Article
Materials Science, Multidisciplinary
Philipp Storm, Susanne Selle, Holger von Wenckstern, Marius Grundmann, Michael Lorenz
Summary: Transparent, p-type semiconductor copper iodide (CuI) thin films were grown via pulsed laser deposition on SrF2(111) using water soluble sacrificial layers of sodium bromide (NaBr). The resulting CuI thin films are single crystalline with reduced surface roughness compared to epitaxial CuI grown with rotational domains on other templates. The CuI thin films were subsequently transferred onto glass using epoxy/glue and dissolution of NaBr in a water-vapor atmosphere.
JOURNAL OF MATERIALS CHEMISTRY C
(2022)
Article
Chemistry, Physical
Zhongguo Li, Zhendong Wu, Xiaolong Wang, Hongtao Cao, Lingyan Liang, Junyi Yang, Yinglin Song
Summary: The study demonstrates the fabrication of amorphous zinc tin oxide thin films with strong visible light absorption using rf magnetron sputtering and rapid postannealing. The ultrafast carrier dynamics of the ternary films were investigated using femtosecond transient absorption spectroscopy, revealing that visible light absorption is induced by band gap reduction rather than defect states in the ZTO film. These findings shed light on the photophysical mechanism of amorphous ZTO films and suggest their potential use in solar cell and photodetector devices.
JOURNAL OF PHYSICAL CHEMISTRY C
(2021)
Article
Chemistry, Physical
Ignas Nevinskas, Zenius Mockus, Remigijus Juskenas, Ricardas Norkus, Algirdas Selskis, Eugenijus Norkus, Atunas Krotkus
Summary: Electron dynamics in polycrystalline bismuth films were investigated by measuring emitted terahertz (THz) radiation pulses after their photoexcitation. The films were grown on metallic substrates by electrodeposition, allowing for more uniform films with consistent grain sizes. It was found that the thermalization of more mobile carriers (electrons) is dominated by carrier-carrier scattering in the THz photoconductivity spectra analysis.
Article
Engineering, Electrical & Electronic
Y. Vygranenko, M. Fernandes, M. Vieira, G. Lavareda, C. Nunes de Carvalho, P. Brogueira, A. Amaral, N. P. Barradas, E. Alves
Summary: This study focuses on the preparation and characterization of undoped and Sn-doped indium sulfofluoride thin films by radio-frequency plasma-enhanced reactive thermal evaporation. The undoped material exhibits a wide range of resistivity depending on deposition conditions, while Sn doping significantly decreases the resistance. Additionally, the synthesized films are highly transparent and exhibit high photosensitivity in the blue-UV region.
MATERIALS SCIENCE IN SEMICONDUCTOR PROCESSING
(2021)
Article
Engineering, Electrical & Electronic
Shuang-Shuang Li, Ming-Yuan Yan, Fang-Yuan Fan, Wei-Qi Dong, Fu-Sheng Luo, Shu-Juan Zhang, Ying Zhang, Lei Chen, Jian-Min Yan, Shan-Tao Zhang, Fei-Fei Wang, Ren-Kui Zheng
Summary: Rare-earth ion doping improves the crystallinity and electrical performance of RxBa1-xSnO3 films. A rule is discovered that the resistivity and metal-semiconductor transition temperature increase with the atomic number of rare-earth ions. Among the four rare-earth ion dopings, La-doping is the most effective approach.
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
(2023)
Article
Chemistry, Physical
Mingming Chen, Xuemin Shen, Chen Zhou, Dawei Cao, Wei Xue
Summary: A high-performance self-powered UV photodetector based on ferroelectric PZT thin films has been fabricated, simplifying device structure and fabrication process. The unique bulk photovoltaic effect of ferroelectric materials can enhance device performance compared to complex device structures. Additionally, the self-powered photocurrent is further enhanced when downward polarizing the PZT thin film.
JOURNAL OF ALLOYS AND COMPOUNDS
(2022)
Article
Nanoscience & Nanotechnology
Wenrui Zhang, Wei Wang, Jinfu Zhang, Tan Zhang, Li Chen, Yu Zhang, Yanwei Cao, Li Ji, Jichun Ye
Summary: By establishing a low-defect diffusion barrier, the responsivity and response time of ε-Ga2O3 MSM photodetectors were improved simultaneously.
ACS APPLIED MATERIALS & INTERFACES
(2023)
Article
Engineering, Electrical & Electronic
Kota Hanzawa, Hidenori Hiramatsu
Summary: LaWN3 epitaxial thin films were successfully grown on α-Al2O3 (0001) substrates using a multi-cathode RF magnetron sputtering gun system with metal targets and nitrogen gas. The films exhibited n-type degenerate semiconducting behaviors, an enlarged optical band gap, and superconductivity at 0.73 K. However, they did not show the predicted ferroelectric properties due to off-stoichiometry. Alternative growth processes are needed to decrease carrier density and achieve ferroelectricity.
ACS APPLIED ELECTRONIC MATERIALS
(2023)
Article
Chemistry, Physical
Laura M. Jacoby, Matthew J. Crane, Daniel R. Gamelin
Summary: This research discovers the potential application of vapor-deposited CsPbBr3 thin films in optoelectronic and spin-based devices. Both photogenerated holes and electrons show coherent spin precession, but the spin dephasing time of photogenerated electrons is shorter.
CHEMISTRY OF MATERIALS
(2022)
Article
Optics
Enrico G. Carnemolla, Wallace Jaffray, Matteo Clerici, Lucia Caspani, Daniele Faccio, Fabio Biancalana, Clayton Devault, Vladimir M. Shalaev, Alexandra Boltasseva, Marcello Ferrera
Summary: Research shows that in the near-zero-index regime, using aluminum zinc oxide thin films can generate radiation tunable in the visible spectral region with a maximum frequency conversion efficiency of 2%. Effective idler wavelength tuning can also be achieved by operating on the temporal delay.
Article
Nanoscience & Nanotechnology
Woo-Jin Lee, Sang-Seok Lee, Sang-Hyun Sohn, Yuna Choi, Il-Kyu Park
Summary: This study reports the effective control of persistent photoconductivity in Zn-doped SnO2 thin films and the enhancement of the performance of solar-blind UV photodetectors. Zn doping plays a critical role in reducing dark current and persistent photoconductivity, thereby increasing photosensitivity and shortening response times.
Article
Chemistry, Physical
Fangjuan Geng, Yu-Ning Wu, Daniel Splith, Liangjun Wang, Xiaowan Kang, Xiaojian Chen, Pengsheng Guo, Shanshan Liang, Lei Yang, Michael Lorenz, Marius Grundmann, Jiaqi Zhu, Chang Yang
Summary: By developing an amorphous Cu(S,I) material system, record high hole conductivities of 10(3)-10(4) S cm(-1) have been achieved in p-type amorphous transparent conductors (a-TCs), making them comparable with commercial n-type TCs made of indium tin oxide and 100 times greater than any previously reported p-type a-TCs. The high hole conduction is due to the overlap of large p-orbitals of I- and S2- anions, providing a hole transport pathway insensitive to structural disorder. Additionally, the bandgap of amorphous Cu(S,I) can be modulated from 2.6 to 2.9 eV by increasing the iodine content. These unique properties demonstrate the great potential of the Cu(S,I) system as a promising p-type amorphous transparent electrode material for optoelectronics.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2023)
Article
Chemistry, Multidisciplinary
Anish Philip, Ramin Ghiyasi, Maarit Karppinen
Summary: Curcumin, known for its antimicrobial effects, is embedded in TiO2 using ALD/MLD thin-film technique to create different superlattice structures for potential synergistic effects. The extension of light absorption to the entire visible range is shown, suggesting the possibility of using these films for light-driven pathogen destruction.
Article
Energy & Fuels
Bat-El Cohen, Ron Alafi, Jonathan Beinglass, Adva Shpatz Dayan, Oren Goldberg, Shachar Gold, Isaac Balberg, Leeor Kronik, Lioz Etgar, Oded Millo, Doron Azulay
Summary: This study investigates the effect of in-gap states on recombination rates in quasi-2D lead-iodide-based perovskites intercalated with various spacer molecules using scanning tunneling spectroscopy, temperature-dependent photoconductivity measurements, and theoretical calculations. Shallow in-gap states are found to dominate the recombination kinetics of photogenerated carriers in these systems.
Article
Chemistry, Multidisciplinary
Samantha M. Harvey, Daniel W. Houck, Wen Liu, Yuzi Liu, David J. Gosztola, Brian A. Korgel, Michael R. Wasielewski, Richard D. Schaller
Summary: CuInSe2 nanocrystals with tunable near-infrared bandgaps show potential for photovoltaic applications and as substitutes for toxic semiconductor compositions. The presence of ligands during synthesis introduces nonradiative electronic states, impacting carrier dynamics and leading to low photoluminescence quantum yields. Carrier lifetimes are influenced by the type of ligand, with rapid trapping observed in certain cases.
Article
Materials Science, Multidisciplinary
Chandra Prakash, Ankit K. Yadav, Ambesh Dixit
Summary: This study investigates the influence of crystallinity on the coexistence of negative differential resistance (NDR) and write once read many (WORM) resistive switching in Cu/BiFeO3/FTO memory devices. It is found that devices with crystalline BiFeO3 exhibit higher peak and valley voltages but higher power consumption compared to devices with amorphous BiFeO3. By manipulating the crystallinity of the active material, different switching characteristics in BiFeO3 can be tailored.
APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING
(2023)
Article
Chemistry, Physical
Jitendra Kumar Yadav, Bharti Rani, Ambesh Dixit
Summary: Rechargeable iron ion batteries were fabricated using mild steel as the negative electrode and vanadium penta oxide as the positive electrode. The performance degradation was investigated without the need for an inert atmosphere. The capacity of the battery decreased to 41% after 30 cycles due to corrosion of the mild steel and the formation of iron-vanadium-based oxides at the cathode end.
Article
Physics, Applied
Surbhi Ramawat, Sumit Kukreti, Abhijeet J. J. Kale, Rajeev Dutt, Aparna Chakrabarti, Ambesh Dixit
Summary: Cs2KMnCl6 is a stable 3d half-metal with high magnetic moment and ferromagnetic properties at high temperatures, as well as 100% spin polarization and high-speed conduction electrons, making it a promising candidate for spintronics.
JOURNAL OF APPLIED PHYSICS
(2023)
Article
Chemistry, Physical
Jitendra Kumar Yadav, Bharti Rani, Ambesh Dixit
Summary: This study fabricated non-aqueous rechargeable iron ion batteries using two-dimensional graphitic carbon nitride as the cathode material. The batteries showed good performance with a specific capacity of 130 mAh/g and capacity retention of over 50% after 100 cycles. The use of this cathode material also demonstrated excellent rate capability with a capacity retention of 60 mAh/g after 240 cycles at a higher current density. The research highlights the potential of 2D graphitic carbon nitride as an efficient cathode material for next-generation energy storage devices.
JOURNAL OF POWER SOURCES
(2023)
Article
Physics, Condensed Matter
Jeel Swami, Ambesh Dixit, Brajesh Tiwari
Summary: The magnetic ground state of the LaCrO3 and CaCrO3 solid solution, La1-xCaxCrO3 (@ 0 <= x <= 1), is investigated in this study to understand the magnetic phase transitions with Ca substitution. Using density functional theory with Hubbard correction, the system exhibits transitions from antiferromagnetic insulator (x = 0) to ferromagnetic half metal (x = 0.75) to antiferromagnetic metal (x = 1). The introduction of Hubbard energy U and Ca substitution affects the Cr-O hybridization, as observed in the partial density of states. The study presents a compositional phase diagram with the magnetic ground state for the La1-xCaxCrO3 (0 <= x <= 1) system.
PHYSICA STATUS SOLIDI B-BASIC SOLID STATE PHYSICS
(2023)
Article
Instruments & Instrumentation
R. M. Sahani, Arun Pandya, Ambesh Dixit
Summary: We prepared a ZnO-6LiF composite using a solution mixing process, with a polystyrene polymer as the host. The composite showed enhanced scintillation pulse heights when compared to pure ZnO or natural LiF. The results demonstrate the potential of the ZnO-6LiF/PS composite for detecting thermal neutron radiation when coupled to a PMT.
REVIEW OF SCIENTIFIC INSTRUMENTS
(2023)
Article
Chemistry, Physical
Chandra Prakash, Priyambada Sahoo, Ramesh Yadav, Akhilesh Pandey, Vijay K. Singh, Ambesh Dixit
Summary: Developing an efficient and inexpensive electrocatalyst is crucial for the green hydrogen economy. The study demonstrates a large-scale, industrially viable synthesis of Zn-doped NiS electrocatalyst on nickel foam through a hydrothermal technique. The catalyst shows excellent catalytic efficacy for both oxygen and hydrogen evolution reactions, with low overpotentials.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2023)
Article
Physics, Applied
Chandra Prakash, Ambesh Dixit
Summary: Researchers successfully synthesized low-cost Cu/CuO/FTO-based devices and investigated their characteristics for neuromorphic computing. These devices exhibited excellent bipolar analog RRAM characteristics and demonstrated remarkable mimicking ability similar to the human brain, substantiating their recognition ability. This study provides a detailed understanding of CuO active material-based resistive switching and its potential for neuromorphic computing beyond the von Neumann architecture.
JOURNAL OF APPLIED PHYSICS
(2023)
Article
Physics, Applied
Sayan Ghosh, C. Sudarshan, C. Sudakar
Summary: This study investigates how sintering conditions and grain boundary engineering can improve the ionic conductivity of LATP ceramics. By using Raman spectroscopy, the changes in vibrational mode characteristics of LATP ceramics with temperature are monitored, revealing the influence of sintering conditions on ionic migration and conductivity.
JOURNAL OF APPLIED PHYSICS
(2023)
Article
Materials Science, Ceramics
Kumar Brajesh, Sudhir Ranjan, Rishow Kumar, Rajeev Gupta, Ambesh Dixit, Ashish Garg
Summary: In this manuscript, the room-temperature properties of CuO and Cu0.995La0.005O ceramics synthesized by solid-state reaction method were investigated. La doping in CuO leads to the evolution of compact and dense microstructure with reduced porosity. The La doping induces strain in the CuO lattice resulting in a reduction in the lattice parameters and cell volume. The dielectric constant of Cu0.995La0.005O ceramics is enhanced and the leakage current is reduced, attributed to the dense microstructure and strain in CuO lattice after La doping. The bandgap of Cu0.995La0.005O ceramics decreases due to increased vacancy defect concentration, and the magnetic and dielectric properties are correlated with the grain size in La-doped CuO.
JOURNAL OF THE AMERICAN CERAMIC SOCIETY
(2023)
Article
Materials Science, Multidisciplinary
Y. Lokeswararao, Athrey C. Dakshinamurthy, Akshay Kumar Budumuru, C. Sudakar
Summary: This study examines the electrochemical performances of Li3V2(PO4)(3) with thin-carbon coating (LVP/C) in nanoparticulate (LVP/C-np) and nanofibrous (LVP/C-nf) morphologies synthesized using sol-gel and electrospinning processes, respectively. The results show that the nanoparticle cathodes exhibit higher capacity fading than the nanofibrous cathodes with increasing C-rate. LVP/C-np and LVP/C-nf cathodes exhibit a discharge capacity of 137 mA h g(-1) and 124 mA h g(-1) at 0.1 C rate.
MATERIALS RESEARCH BULLETIN
(2023)
Article
Instruments & Instrumentation
Kiran Ahlawat, Ramavtar Jangra, Ambar Ish, Ambesh Dixit, Deepak Fulwani, Neha Jain, Ram Prakash
Summary: This study presents a large-scale surface disinfection system that utilizes UV-C light and nanotechnology in a highly protective biosafety environment. By generating hydroxyl radicals and negative air ions, this system can effectively deal with shadow regions and achieve over 95% bacterial inactivation efficiency.
REVIEW OF SCIENTIFIC INSTRUMENTS
(2023)
Review
Materials Science, Multidisciplinary
Priyambada Sahoo, Lokesh Saini, Ambesh Dixit
Summary: Implementation of stealth features for advanced airborne platforms is essential for each country to prevent/delay detection by enemy radars during tactical missions. The use of microwave-absorbing materials (MAMs) on identified locations is the only viable solution to reduce the radar cross-section (RCS) and achieve stealth capabilities. This review provides a comprehensive overview of the range of materials used as MAMs, along with their microwave loss mechanisms, filling the knowledge gap in this area. The current limitations and future prospects for the development of stealth materials are also discussed.
OXFORD OPEN MATERIALS SCIENCE
(2023)
Article
Chemistry, Physical
Chandra Prakash, Ankit K. Yadav, Ambesh Dixit
Summary: In this study, the resistive random access memory characteristics of a Cu/BFO/PMMA/ITO/PET device configuration were demonstrated on a flexible substrate. The device exhibited non-volatile bipolar resistive switching with good repeatability and coexistence of NDR for 100 cycles or more. The device retained its read state for 10^4 seconds or more and successfully switched between states without affecting memory characteristics. The study also showed the possibility of integrating BFO with flexible substrates for hybrid organic/inorganic memory structures.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2023)
Article
Chemistry, Multidisciplinary
Akshay Kumar Budumuru, Lokeswararao Yelamnchi, Chandran Sudakar
Summary: Sb1.9Al0.1S3 nanorods with constrained cutoff voltage in the alloying regime exhibit excellent electrochemical performance, providing an initial capacity of around 450 mA h g(-1) and showing excellent cycling stability with 63% retention (around 240 mA h g(-1) after 1000 cycles at 5C-rate) compared to 71.4 mA h g(-1) after 500 cycles observed in full-regime cycling. The formation of crystalline Sb(Al) in Sb1.9Al0.1S3 and the retention of nanorod microstructure enhance its performance, while Sb2S3 nanorod electrodes get pulverized and show microcracks. Percolating Sb nanoparticles buffered by the Li2S matrix and other polysulfides contribute to the improved performance of the electrode. These findings pave the way for high-energy and high-power density LIBs with alloy anodes.
NANOSCALE ADVANCES
(2023)
