Article
Materials Science, Multidisciplinary
Qais M. Al-Bataineh, Ahmad A. Ahmad, Ihsan A. Aljarrah, Ahmad M. Alsaad, Ahmad Telfah
Summary: This study investigates the impact of hydrogen and nitrogen impurities on the physical properties of transparent conductive oxides. The annealing of (Cu-Ni)/ZnO films under different atmospheres leads to the formation of different defects, resulting in changes in conductivity type and optical properties.
APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING
(2022)
Article
Physics, Multidisciplinary
Arya Sukumaran, N. Sivanantham, E. Vinoth, N. Gopalakrishnan
Summary: This paper reports on the room temperature ferromagnetism in Y-doped ZnO thin films grown by RF magnetron sputtering. Characterization techniques including XRD, Raman spectroscopy, XPS, FESEM, EDAX, photoluminescence spectroscopy, and EPR spectroscopy were used to study the crystal structure, electronic states, morphology, point defects, and magnetic properties of the films. It was found that zinc interstitial and oxygen vacancy defects play a crucial role in the ferromagnetic properties of Y-doped ZnO thin films. VSM analysis confirmed the ferromagnetic nature of the doped films, while the pure ZnO film exhibited diamagnetic behavior. A dual donor defect-assisted bound magnetic polaron model was proposed to explain the behavior of the Y-doped ZnO diluted magnetic semiconductor system. The results obtained were found to be reliable and reproducible.
Article
Materials Science, Multidisciplinary
Leonie Koch, Sebastian Steiner, An-Phuc Hoang, Arne J. Klomp, Karsten Albe, Till Froemling
Summary: Solid solutions of sodium bismuth titanate (NBT) are the most performant lead-free dielectric ceramics for energy storage. The defect chemistry of NBT is complex, and acceptor doping can result in unexpected and extraordinarily high oxygen ionic conductivity. This study elucidates the interaction between acceptors and oxygen vacancies and rationalizes the observed differences in conductivity through experiments and calculations.
Review
Materials Science, Ceramics
Vitaly Gurylev, Tsong Pyng Perng
Summary: Defects in zinc oxide (ZnO) play a crucial role in influencing its properties and applications, with potential for improved characteristics through the introduction of oxygen and zinc vacancies. Defective ZnO shows broad application potential in nanoscale devices, yet faces challenges and requires further research for in-depth exploration.
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
(2021)
Article
Chemistry, Multidisciplinary
D. Mahato, T. Gurusamy, S. K. Jain, K. Ramanujam, P. Haridoss, T. Thomas
Summary: The sluggish nature of oxygen reduction reaction (ORR) and the current use of expensive precious metals (platinum [Pt], palladium [Pd], etc.) are barriers to the commercialization and scale-up of fuel cell and metal-air battery technologies. Given this, the development of low-cost non-precious metal-based electrocatalysts with high activity and durability is an area that requires attention. In this study, a cupric oxide (CuO) modified zinc oxide (ZnO) supported on nitrogen-doped carbon (CuO/ZnO/NC-60 0) was reported as a desirable electrocatalyst due to its activity in alkaline medium, durability, and low cost.
MATERIALS TODAY CHEMISTRY
(2022)
Article
Chemistry, Physical
Anastasia V. Egorova, Ksenia G. Belova, Irina E. Animitsa
Summary: The LaIn1-xZnxO3-1/2x samples were synthesized for the first time via solid-state reaction method. The effect of Zn2+ doping on the structure, water uptake and electrical properties of LaInO3 was investigated. The results show that Zn2+ is a good alternative to alkaline earth metals and improves the conductivity of the ceramics. The phase exhibits oxygen-ionic transport at temperatures below 500°C and protonic transport at temperatures below 600°C.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2023)
Article
Engineering, Environmental
Wenbo Qin, Zhenyu Yuan, Yanbai Shen, Renze Zhang, Fanli Meng
Summary: In this study, P-doped perovskite LaFe1-xPxO3-delta with abundant Ov defects were prepared and utilized as sensors for acetone detection. The LaFe0.99P0.01O3-delta sensor exhibited excellent gas-sensitive performance, with nearly twofold improvement in response value and a detection limit at the ppb level. Electron paramagnetic resonance and X-ray photoelectron spectroscopy confirmed the strong correlation between the sensing characteristics and the Ov defects. Theoretical analysis revealed that P doping induced Ov defects and modulated the energy levels of the material, enhancing chemisorbed oxygen species and intermolecular interactions.
CHEMICAL ENGINEERING JOURNAL
(2022)
Article
Engineering, Electrical & Electronic
Angang Song, Guoqin Cao, Di Zhu, Baofeng Zhao, Zhenya Fu, Shuaiqi Cao, Qingjie Wang, Junhua Hu
Summary: Nb-doped TiO2 thin films were prepared by sputtering and optimized through annealing for photoelectric cooperation. The flow of oxygen during deposition was found to greatly affect the transparent conductivity, and oxygen vacancies were related to phase transitions. The chemical states of Nb, Ti, and O before and after annealing were discussed.
JOURNAL OF ELECTRONIC MATERIALS
(2022)
Article
Engineering, Electrical & Electronic
Shuang Yang, Huazhi Gu, Ao Huang
Summary: C-Al co-doped ZnO films deposited at oxygen partial pressure range of 1-7 Pa by pulse laser deposition exhibit superior optical and electrical properties. The films show improved crystallinity and grain size at 1-3 Pa compared to AZO films, and carbon doping significantly enhances the optical and electrical properties. The lowest resistivity of 3.1x10-4 omega cm is achieved at 1 Pa, with an average transmittance higher than 85% and optimal value of 89.9%.
MATERIALS SCIENCE IN SEMICONDUCTOR PROCESSING
(2021)
Article
Materials Science, Multidisciplinary
Chaeseon Hong, Kyung-Mun Kang, Minjae Kim, Yue Wang, Taehee Kim, Chan Lee, Hyung-Ho Park
Summary: Si-doped zinc oxide thin films were fabricated using atomic layer deposition, with Si concentration controlled by changing the Si pulse cycle. As Si-doping concentration increased, film crystallinity deteriorated but electrical characteristics improved. The films showed a hexagonal wurtzite structure with good transmittance and an increased band gap.
MATERIALS SCIENCE AND ENGINEERING B-ADVANCED FUNCTIONAL SOLID-STATE MATERIALS
(2021)
Article
Physics, Applied
Chih-Ming Lin, Yu-Chin Tseng, Yi-Jia Tsai, Yu-Sheng Lin, Sheng-Rui Jian, Yu-Chun Chuang, Jenh-Yih Juang
Summary: In situ angle-dispersive X-ray diffraction study revealed that transition metal doping can significantly reduce the onset pressure of ZnO's pressure-driven phase transition from fourfold to sixfold structure. The transition path is influenced by the specific transition metal element. The doping-induced lattice distortion and the amount of 3d electrons carried by the transition metal atom both play important roles in the mechanism of the phase transition.
APPLIED PHYSICS LETTERS
(2023)
Article
Chemistry, Physical
Xixi Ren, Yugang Gao, Liren Zheng, Zeyan Wang, Peng Wang, Zhaoke Zheng, Yuanyuan Liu, Hefeng Cheng, Ying Dai, Baibiao Huang
Summary: Oxygen vacancy defect engineering, achieved through Ce3+ doping in ZnO, allows for controlled manipulation of defect concentration, impacting the performance of electrocatalytic CO2 reduction to CO. High concentrations of oxygen vacancies in Ce0.016Zn0.984O were found to enhance CO2 adsorption and activation capability, leading to optimized CO2 reduction to CO performance.
SURFACES AND INTERFACES
(2021)
Article
Engineering, Environmental
Zishuo Li, Xianghong Liu, Miao Zhou, Shoulong Zhang, Shize Cao, Guanglu Lei, Chengming Lou, Jun Zhang
Summary: This study presents a high-performance gas sensor based on plasma-etched zinc oxide thin films, with a thickness of 20 nm deposited on SiO2 wafers by ALD. The zinc oxide sensor exhibits n-type conductivity and sensitivity to triethylamine, with the sensor response affected by annealing temperature. Ar plasma treatment results in improved sensor performance by generating oxygen vacancies.
JOURNAL OF HAZARDOUS MATERIALS
(2021)
Article
Materials Science, Multidisciplinary
Adriana Martinez Oviedo, Hien Truong Thi, Quang Chau Van, Hao Huy Nguyen
Summary: By investigating the physicochemical properties of Fe-doped TiO2, it was found that the material possessed defect structures including oxygen vacancies, Ti3+, and Fe ions. These defect structures prevented electron-hole recombination, thereby enhancing the lifetime of the photoelectrons. As a result, the efficiency of Fe-TiO2-based DSSC increased to 30% compared to undoped-TiO2-based DSSC.
Article
Materials Science, Ceramics
M. Kumar, Mohinder Singh Chauhan, M. Shaheer Akhtar, Ahmad Umar
Summary: Nanostructured ZnO doped with different Ce precursor concentrations were prepared and tested for photocatalytic and chemical sensing performances. Blue-shift was detected in 5 mol% Ce doping, which was found to be the optimum concentration for achieving the maximum dye degradation and sensing performances. Facile redox couple Ce3+/Ce4+ improved charge separation, leading to increased catalytic and PA sensing performances.
CERAMICS INTERNATIONAL
(2021)
Article
Chemistry, Multidisciplinary
Jae Ho Jeon, Hong Ryeol Na, Heeju Kim, Sunghun Lee, Sehwan Song, Jiwoong Kim, Sungkyun Park, Jeong Kim, Hwayong Noh, Gunn Kim, Sahng-Kyoon Jerng, Seung-Hyun Chun
Summary: A robust topological Hall effect has been observed in bilayers of a ferromagnet and a noncoplanar antiferromagnet due to the interfacial Dzyaloshinskii-Moriya interaction. This provides a new mechanism towards topologically protected magnetic structures.
Article
Physics, Multidisciplinary
Bo Hyeon Kim, Sam Yeon Cho, Eun-Young Kim, Sang Don Bu
Summary: One-dimensional PbTiO3 nanotubes were fabricated via hydrothermal method and the morphology of the nanotube arrays was successfully controlled by adjusting reaction conditions.
JOURNAL OF THE KOREAN PHYSICAL SOCIETY
(2023)
Article
Chemistry, Multidisciplinary
Seungmo Yang, Tae-Seong Ju, Changsoo Kim, Hyun-Joong Kim, Kyongmo An, Kyoung-Woong Moon, Sungkyun Park, Chanyong Hwang
Summary: This study presents a method for creating magnetic skyrmions in typical perpendicular magnetic anisotropy films and determines the magnitude of the required external magnetic fields. Additionally, the study explores the dependence of the minimum size of skyrmions on the magnetic anisotropy.
Article
Engineering, Environmental
Hyun Ho Lee, Yong Dong Noh, Do Yeong Hur, Sungkyun Park, Sehwan Song, Jong-Seong Bae, Hojeong Kang, Sung Un Kim, Chang Oh Hong
Summary: This study evaluated the reducing effects of calcite and phosphogypsum on the availability of arsenate [As(V)] to plants and investigated the mechanisms of As(V) immobilization. The presence of 1% calcite and phosphogypsum in upland arable soils decreased the availability of As(V) to plants by 17.4% and 36.9% respectively, compared to the control. The immobilization of As(V) depends on soil pH and the type of calcium material used.
JOURNAL OF HAZARDOUS MATERIALS
(2023)
Article
Chemistry, Physical
Won-Jang Cho, Seok-Kyu Cho, Jun Hyuk Lee, Jeong Hoon Yoon, Sangwoo Kwon, Chanui Park, Won Bo Lee, Pil J. Yoo, Minjae Lee, Sungkyun Park, Tai Hui Kang, Gi-Ra Yi
Summary: In this study, nanostructured solid polymer electrolytes (SPEs) with functionally separated ion transporting channels and solid-phase walls were successfully synthesized. These SPEs exhibit high ionic conductivity and mechanical strength, and show promising performance in solid-state lithium metal batteries.
JOURNAL OF MATERIALS CHEMISTRY A
(2023)
Review
Energy & Fuels
Saravanan Nagappan, Malarkodi Duraivel, Vijayakumar Elayappan, Nallal Muthuchamy, Balaji Mohan, Amarajothi Dhakshinamoorthy, Kandasamy Prabakar, Jae-Myung Lee, Kang Hyun Park
Summary: Recently, metal-organic frameworks (MOFs)-based cathode materials have gained significant attention for their high surface area, controlled architecture, porosity, and tunability. By altering the synthesis techniques, the performance of MOF-based cathodes can be improved for specific battery applications. The review article provides a comprehensive overview of the uniqueness and history of MOF-based cathodes, their advantages and disadvantages, various synthesis approaches, and their use in different battery applications.
Article
Nanoscience & Nanotechnology
Muthuchamy Nallal, Kang Hyun Park, Sungkyun Park, Jaeyong Kim, Sulakshana Shenoy, Chitiphon Chuaicham, Keiko Sasaki, Karthikeyan Sekar
Summary: Hierarchical Cu2O/RGO nanocomposites synthesized via a sustainable photoredox strategy exhibit excellent performance as bifunctional electrocatalysts for oxygen and hydrogen evolution reactions (OER and HER) under alkaline conditions. The Cu2O/RGO electrocatalyst shows small overpotentials, fast kinetics, high mass performance, long-term stability, and high Faradaic efficiency, surpassing other reported electrocatalysts.
ACS APPLIED NANO MATERIALS
(2022)
Article
Chemistry, Physical
Sungbin Im, Sam Yeon Cho, Jae-Hyeon Cho, Geon-Tae Hwang, Angus I. Kingon, Sang Don Bu, Wook Jo, Seung-Hyun Kim, Chang Kyu Jeong
Summary: The study focuses on the application of piezoelectric nanocomposites consisting of a polymer matrix and ceramic fillers in flexible, wearable, and self-powered electronic devices. The researchers found that a relaxor ferroelectric terpolymer matrix can enhance the piezoelectric output, leading to improved energy harvesting and sensor performance. This research provides important physical information about the interface between the polymer matrix and ceramic fillers in flexible piezoelectric nanocomposite applications.
APPLIED SURFACE SCIENCE
(2023)
Article
Electrochemistry
Karkuzhali Rajendran, Muthuchamy Nallal, Muthusankar Ganesan, Manoj Shanmugasundaram, Shamim Ahmed Hira, Gopu Gopalakrishnan, Sethupathi Murugan, Gedanken Aharon, Kang Hyun Park
Summary: In this study, a three-dimensional hybrid nanocomposite (3D-CeVO4/MWNT HNC) was developed, which exhibited excellent properties for energy storage and sensors. It is considered to be the best material to overcome the future energy demand and economic crisis.
ELECTROCHIMICA ACTA
(2023)
Article
Chemistry, Multidisciplinary
Saravanan Nagappan, Malarkodi Duraivel, SeongHoon Han, Mohammad Yusuf, Manjiri Mahadadalkar, KyeongMun Park, Amarajothi Dhakshinamoorthy, Kandasamy Prabakar, Sungkyun Park, Chang-Sik Ha, Jae-Myung Lee, Kang Hyun Park
Summary: Graphene, a two-dimensional material with a large surface area, is widely used in various fields. Recently, there has been increased focus on developing metal-free graphenes doped with heteroatoms as efficient electrocatalysts for oxygen reduction reactions (ORRs). Our study found that graphene prepared from graphene oxide (GO) by pyrolysis under a nitrogen atmosphere at 900 degrees C showed better ORR activity compared to pristine GO. Various pyrolysis conditions were tested, and the results suggest that the ORR electrocatalytic activity of graphene is influenced by these conditions. The prepared graphenes, particularly G100-1B and G100-2B, displayed promising ORR activity for fuel cell and metal-air battery applications.
Article
Chemistry, Multidisciplinary
S. Nagappan, M. Duraivel, N. Muthuchamy, S. H. Han, B. Mohan, S. Park, K. Prabakar, J-M. Lee, K. H. Park
Summary: Recently, there has been a lot of interest in the development of biodegradable polymer-derived and heteroatom-doped carbon-Fe3O4 electrocatalysts due to their easy manufacturing, biocompatibility, environmental friendliness, and ability to induce porosity. A highly stable and hierarchical N-doped carbon-Fe3O4 electrocatalyst was created through pyrolysis of a chitosan gel membrane with 2 (w/v)% ferric chloride hexahydrate at different temperatures. The addition of Fe to the chitosan significantly improved the electrocatalytic activity for the oxygen reduction reaction (ORR), presenting a new opportunity for further applications.
MATERIALS TODAY CHEMISTRY
(2023)
Review
Public, Environmental & Occupational Health
Ananda Babu Sairam, Anandhavelu Sanmugam, Ashwini Pushparaj, Gaayathri Mahesh Kumar, Nithila Sundarapandian, Sulakshuna Balaji, Muthuchamy Nallal, Kang Hyun Park
Summary: The demand for drug delivery systems (DDSs) has increased due to the ambiguity of certain diseases and the potential toxicity of many medicines. Nanomedicine, specifically the use of nanocarriers and medication formulations, has become a unique concept for enhanced drug bioaccessibility, long-term drug administration, and dose reduction. Among various nanomedicine techniques, polymeric nanoparticles (poly-NPs) have shown great potential in improving drug pharmacokinetics. However, the safety and toxicity of poly-NPs in long-term studies using high doses remain poorly understood. This article discusses the toxicity of nanoparticles (NPs) used in DDSs, including polylactide-co-glycolide, polylactic acid, polycaprolactone, and poly(alkyl cyanoacrylates).
ACS CHEMICAL HEALTH & SAFETY
(2023)
Article
Environmental Sciences
Manjiri A. Mahadadalkar, NaHyun Park, Mohammad Yusuf, Saravanan Nagappan, Muthuchamy Nallal, Kang Hyun Park
Summary: Water pollution caused by industrial wastewater is a critical environmental problem. Synthetic dyes used in various industries have complex composition, high toxicity, and low biodegradability, causing negative impacts on ecosystems. To address this issue, TiO2 fibers photocatalyst doped with Fe was synthesized using sol-gel and electrospinning techniques for the degradation of dyes. The fabricated fibers showed excellent photocatalytic degradation activity, with 99% degradation of rhodamine B in 120 minutes. The fibers also demonstrated good photocatalytic activity even after 5 cycles of reuse.
Article
Chemistry, Inorganic & Nuclear
Balaji Mohan, Kyung Hee Oh, Kyeongmun Park, Mohammad Yusuf, Ji Chan Park, Kang Hyun Park, Buhyun Youn
Summary: In this study, hollow cubic Cu(x)O nanoparticles (approx. 23 nm) incorporated with CNF (HC-Cu(x)O/CNF) were fabricated by the controlled thermal oxidation of solid cubic Cu2O nanoparticles (approx. 21 nm) supported on carbon nanofibers (SC-Cu2O/CNF) under airflow. These hollow Cu(x)O nanocubes with increased surface areas exhibited excellent catalytic activity for unsymmetrical chalcogenide synthesis under ligand-free conditions. The synthesis process involved the transformation of solid Cu(2)O cubes/CNF to hollow Cu(x)O cubes/CNF through thermal oxidation, utilizing the Kirkendall effect.
INORGANIC CHEMISTRY
(2023)
Article
Chemistry, Multidisciplinary
Sulakshana Shenoy, Chitiphon Chuaicham, Keiko Sasaki, Sungkyun Park, Muthuchamy Nallal, Kang Hyun Park, Karthikeyan Sekar
Summary: A novel one-pot synthesis method was proposed for designing bimetallic oxide-nitride electrocatalysts with tunable morphologies. The method showed remarkable catalytic efficacy and stability without the need for a distinct nitridation process.
CHEMICAL COMMUNICATIONS
(2023)
