Article
Nanoscience & Nanotechnology
Kota Udagawa, Mariko Murayama, Xinwei Zhao
Summary: In this study, Co-doped ZnO thin films were fabricated using pulsed laser deposition under different oxygen partial pressures. The research found that the valence state of Co ions was 2+ and the number of oxygen vacancies increased with lowering oxygen partial pressure. The substitution of Co2+ ions for Zn sites in the ZnO lattice was confirmed by UV-visible absorption spectroscopy. The Co-doped ZnO thin films exhibited ferromagnetism at room temperature, and the saturation magnetization showed a strong correlation with the number of oxygen vacancies.
Article
Nanoscience & Nanotechnology
Chengtao Xia, Jinxin Chen, Tong Zhao, Linlin Fan, Deren Yang, Xiangyang Ma
Summary: This study reports on a LED based on erbium-doped zinc oxide/SiO2/n(+)-Si heterostructure, with a significant enhancement of erbium-related emissions achieved through titanium codoping.
ACS APPLIED MATERIALS & INTERFACES
(2022)
Article
Materials Science, Multidisciplinary
Abdel Khaleq Mousa Alsmadi, Belal Salameh, Maryam Barhoush
Summary: In this study, high-quality copper-doped ZnO films were prepared using the standard spray pyrolysis method. The correlation between magnetic ordering and native defect states in the ZnO lattice was systematically investigated. The results showed that the detected ferromagnetic ordering is intrinsic and induced by the copper dopants. An improvement in ferromagnetic ordering was observed with increasing copper dopant concentration, which was correlated with an increase in oxygen vacancy and zinc interstitial concentrations and a slight decrease in the concentration of zinc vacancies and oxygen interstitial levels. The magnetic ordering mechanism was associated with the long-range ferromagnetic coupling between copper ions mediated by intrinsic defects.
Article
Chemistry, Physical
Brahim Marfoua, Jisang Hong
Summary: Despite efforts to find room temperature ferromagnetic 2D materials, only a few have been synthesized. A recent study confirmed room temperature ferromagnetism in a multilayer structure. However, calculations showed an antiferromagnetic ground state in the monolayer and bilayer systems. Further investigation revealed that hydrogen-induced ferromagnetism was possible. The resulting systems showed a ferromagnetic ground state and optically transparent behavior.
APPLIED SURFACE SCIENCE
(2023)
Article
Materials Science, Multidisciplinary
Li-Yan Hu, Li-Fang Yu, Huan Yang, Xian Xu, Fang Wang, Xiao-Hong Xu
Summary: Two-dimensional VSe2 and V1-xFexSe2 nanosheets were synthesized using a high-temperature organic solution method, with tunable thickness and room-temperature ferromagnetism. The enhancement of magnetization in V0.8Fe0.2Se2 nanosheets is attributed to the coupling interaction of 3d orbits between V and Fe atoms, showing 5 times higher coercivity and magnetization compared to pure VSe2 nanosheets.
Article
Materials Science, Multidisciplinary
Cai-Qin Luo, Si-Cong Zhu, Chi Xu, Shengqiang Zhou, Chi-Hang Lam, Francis Chi-Chung Ling
Summary: Using first-principle calculations, the study investigates the magnetic properties of monovacancies and Sb-related defects in ZnO material. Experimental results confirm the ferromagnetic behavior predicted by the calculations, demonstrating the importance of defects containing V-Zn, V-O, Sb-Zn, Sb-O, Sb-Zn-V-Zn, and Sb-Zn-2V(Zn) in influencing magnetic properties.
JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS
(2021)
Article
Chemistry, Physical
A. Di Trolio, A. Amore Bonapasta, C. Barone, A. Leo, G. Carapella, S. Pagano, A. Polimeni, A. M. Testa
Summary: The study reveals that Co doping and H irradiation have significant effects on the resistivity and transport properties of ZnO, with Co increasing the resistivity at high temperatures and H counteracting this effect to some extent. Two different thermally activated processes were identified to govern charge transport in the three materials at high and low temperatures, respectively, and it was found that both Co and H reduce the effects of grain boundaries on the transport processes.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2021)
Article
Chemistry, Physical
M. P. F. de Godoy, X. Gratens, V. A. Chitta, A. Mesquita, M. M. de Lima Jr, A. Cantarero, G. Rahman, J. M. Morbec, H. B. de Carvalho
Summary: This study reports on achieving room temperature ferromagnetism in ZnO samples through Co-doping. By introducing controlled defects via heat treatments in a reductive atmosphere and conducting structural analysis and magnetometry, the magnetic behavior is fully explained in terms of the bound magnetic polaron model. The origin of the observed defect-induced ferromagnetism is attributed to the ferromagnetic coupling between Co ions mediated by magnetic polarons due to zinc interstitial defects.
JOURNAL OF ALLOYS AND COMPOUNDS
(2021)
Article
Multidisciplinary Sciences
Rui Chen, Fuchuan Luo, Yuzi Liu, Yu Song, Yu Dong, Shan Wu, Jinhua Cao, Fuyi Yang, Alpha N'Diaye, Padraic Shafer, Yin Liu, Shuai Lou, Junwei Huang, Xiang Chen, Zixuan Fang, Qingjun Wang, Dafei Jin, Ran Cheng, Hongtao Yuan, Robert J. Birgeneau, Jie Yao
Summary: The authors have overcome the limitation of vdWs materials being magnetic only at low temperature, by observing room temperature magnetic ordering in Cobalt doped graphene-like Zinc-Oxide. Through various experimental techniques, they have demonstrated clear evidence of spontaneous magnetization in this new material system at room temperature and above, opening up a new path to 2D ferromagnetism with exceptional tunability and robustness.
NATURE COMMUNICATIONS
(2021)
Article
Chemistry, Multidisciplinary
Guy L. Kabongo, Gugu H. Mhlongo, Mokhotjwa S. Dhlamini
Summary: The research successfully synthesized ZnO nanostructures doped with Holmium, observing changes in morphology and luminescence properties. Reduced surface defects were found in the doped samples through XPS analysis, and enhanced room temperature ferromagnetism correlated with UV-VIS transmittance results was detected in Ho3+-doped ZnO samples.
Article
Chemistry, Physical
Qian Li, Yifan Zhang, Mengdi Zhang, Wei Cheng, Bin Liao, Minju Ying
Summary: Gd-doped and (Al, Gd) codoped ZnO films prepared by ion implantation and radio frequency magnetron sputtering exhibit room temperature ferromagnetism, with magnetization depending on carrier concentration. The magnetic behavior can be explained by the bound magnetic polaron model and carrier-mediated exchange mechanisms.
JOURNAL OF ALLOYS AND COMPOUNDS
(2023)
Article
Physics, Condensed Matter
Xiang Yu, Yang Gao, Shicheng Sun, Qi Sui, Xiaolei Song, Qiuyu Fan
Summary: The Co content plays a crucial role in the magnetic and electric properties of ZnO:Co films. Increasing the Co content leads to higher surface roughness, crystalline size, electrical conductivity, carrier concentration, mobility, and saturation magnetization in the prepared films.
PHYSICA B-CONDENSED MATTER
(2023)
Article
Materials Science, Multidisciplinary
Yulia E. Samoshkina, Irina S. Edelman, Hsiung Chou, Hsien-Chi Lin, Gopeshwar D. Dwivedi, Dmitry A. Petrov, Sergey M. Zharkov, Galina M. Zeer, Maxim S. Molokeev
Summary: (Co + Al)-doped ZnO films synthesized by RF magnetron sputtering in a mixed atmosphere of Ar + H-2 exhibit superior magnetic and optical properties, showing ferromagnetic behavior at room temperature and high electric conductivity. These characteristics are believed to be associated with defect-related mechanisms.
MATERIALS SCIENCE AND ENGINEERING B-ADVANCED FUNCTIONAL SOLID-STATE MATERIALS
(2021)
Article
Materials Science, Multidisciplinary
Guangqiang Mei, Wei Tan, Xingxia Cui, Cong Wang, Qing Yuan, Yafei Li, Cancan Lou, Xuefeng Hou, Mengmeng Zhao, Yong Liu, Wei Ji, Xiaona Zhang, Min Feng, Limin Cao
Summary: Researchers have achieved room-temperature ferromagnetism by doping Fe into SnSe. This ferromagnetic semiconductor has a large bandgap and may be applied in next-generation information device technologies, with the advantage of scalability for industrial production.
MATERIALS TODAY PHYSICS
(2023)
Article
Multidisciplinary Sciences
Yi Zhou, Qing He, Fei Zhou, Xingqi Liao, Yong Liu, Zhonghong Lai, Mingqing Liao, Tianyi Han, Yudong Huang, Jingchuan Zhu
Summary: A dilute magnetic semiconductor based on perovskite niobates has been reported, showing stable local ferromagnetism at room temperature with the addition of Co doping. The material exhibits strong saturation magnetization, remnant magnetization, and small coercive field, indicating potential for practical applications.
ROYAL SOCIETY OPEN SCIENCE
(2021)
Article
Physics, Condensed Matter
Bowen Li, Haoyun Bai, Shiying Shen, Kar Wei Ng, Hui Pan
Summary: In this study, a new group of layered electrides, M2X (M = Ti, V, Cr; X = C, N), with electrons distributed in the interlayer spacings, is reported. It is found that the interstitial electrons tend to be delocalized from the Ti-based structures to the Cr-based ones. The interstitial electrons are shown to originate from the d-electrons of transition metal atoms. These findings demonstrate the existence of tunable interstitial electrons with rich electronic properties in layered MXenes and provide valuable insights into the design and fabrication of new materials with multiple applications.
JOURNAL OF PHYSICS-CONDENSED MATTER
(2023)
Article
Chemistry, Multidisciplinary
Xiaocang Han, Jing-Yang You, Shengqiang Wu, Runlai Li, Yuan Ping Feng, Kian Ping Loh, Xiaoxu Zhao
Summary: Transition-metal trihalides MX3 belong to a family of novel 2D magnets with topological magnons and electromagnetic properties, showing great potential in next-generation spintronic devices. However, direct atomic-scale analysis of MX3 is challenging due to their air instability, making information on stacking-registry-dependent magnetism elusive. In this study, we report a nondestructive transfer method to realize intact transfer of bilayer MX3 and provide a full spectrum of stacking orders in MX3 with atomic precision, revealing their associated magnetic ground states. The study sheds light on the structural basis of diverse magnetic orders in MX3, paving the way for modulating magnetic couplings via stacking engineering.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Materials Science, Multidisciplinary
Saba Khan, Yuan-Ping Feng, Nacir Tit
Summary: Designing 2D materials with half-metallicity is crucial for spintronic devices. By using manganese as a catalyst combined with specific metal atoms, it is possible to achieve half-metallicity, which is attributed to the ferromagnetic coupling interactions between the catalysts and periodic boundaries.
Review
Engineering, Environmental
Mingpeng Chen, Di Liu, Lulu Qiao, Pengfei Zhou, Jinxian Feng, Kar Wei Ng, Qingju Liu, Shuangpeng Wang, Hui Pan
Summary: The dynamical processes in electrochemical reactions in electrocatalysis are not well understood, which leads to wasted efforts in the design of electrocatalysts. However, in-situ/operando Raman technique can provide guidance for the design of electrocatalysts. This review summarizes recent advances of in-situ/operando Raman studies in different electrocatalytic systems and their applications in understanding the mechanisms.
CHEMICAL ENGINEERING JOURNAL
(2023)
Article
Nanoscience & Nanotechnology
Lihong Yin, Zhiqiang Li, Jinxian Feng, Pengfei Zhou, Lulu Qiao, Di Liu, Zhibin Yi, Weng Fai Ip, Guangfu Luo, Hui Pan
Summary: In this study, a Cu-CuInO2 composite catalyst was designed for electrochemical CO2 reduction reaction (e-CO2RR). The catalyst exhibited high selectivity and stability, attributed to the CuInO2 nanoparticles. Experimental and theoretical results confirmed that CuInO2 nanoparticles offer a facile catalyst for e-CO2RR with high selectivity and stability.
ACS APPLIED MATERIALS & INTERFACES
(2023)
Article
Chemistry, Physical
Jinxian Feng, Junyan Li, Lulu Qiao, Dong Liu, Pengfei Zhou, Jun Ni, Hui Pan
Summary: In this work, Cu-incorporated ZnO electrocatalyst (Cu25Zn-A) was synthesized on a Zn plate for electrochemical CO2 reduction reaction (e-CO2RR). The Cu25Zn-A exhibited a high CO Faraday efficiency (>90%) and a CO yield rate of 0.49 mmol cm-2 h-1. The enhanced catalytic activity of Cu25Zn-A was attributed to the presence of Cu steps on the reconstructed surface, which weakened the adsorption of OH-/CO32- and enhanced the adsorption/activation of reactants and stabilization of intermediates. Furthermore, Cu incorporation increased the density of defects in Zn oxide, resulting in improved deoxygenation step. These findings provide valuable insights into the mechanism of CO2 reduction and can guide the design of novel electrocatalysts.
APPLIED CATALYSIS B-ENVIRONMENTAL
(2023)
Article
Physics, Applied
Shiying Shen, Haoqiang Ai, Yandong Ma, Haoyun Bai, Xuejian Du, Feifei Li, Hui Pan
Summary: We report the photovoltaic effect in a feasible TlNbX4O monolayer with large ferroelectric polarization, demonstrating its potential application in high-efficiency solar cells. The TlNbX4O monolayers are identified as ferroelectric semiconductors with moderate switching barriers and higher spontaneous polarizations. Giant shift currents are observed for TlNbCl4O, TlNbBr4O, and TlNbI4O, indicating distinct features of the bulk photovoltaic effect.
APPLIED PHYSICS LETTERS
(2023)
Article
Engineering, Environmental
Chunfa Liu, Jinxian Feng, Pengfei Zhou, Dong Liu, Lulu Qiao, Di Liu, Youpeng Cao, Shi-Chen Su, Hongchao Liu, Hui Pan
Summary: In this study, a series of multi-metal oxide catalysts were designed and prepared on cobalt foams through simple thermal decomposition and electrochemical activation, achieving high efficiency, low cost, and long-term stability. Among them, FeCoCrCuOx@CF showed remarkable catalytic activity and long-term stability for hydrogen evolution reaction (HER). The findings provide new strategies for the design of efficient and stable catalysts for industrial water electrolysis.
CHEMICAL ENGINEERING JOURNAL
(2023)
Article
Chemistry, Physical
Pengfei Zhou, Songbo Chen, Haoyun Bai, Chunfa Liu, Jinxian Feng, Di Liu, Lulu Qiao, Shuangpeng Wang, Hui Pan
Summary: In this study, a simple spontaneous corrosion and cyclic voltammetry (CV) activation method was used to fabricate Zn-incorporated NiFe layered double hydroxide (LDH) on commercial NiFe foam, which showed excellent oxygen evolution reaction (OER) performance.
JOURNAL OF COLLOID AND INTERFACE SCIENCE
(2023)
Article
Chemistry, Physical
Lulu Qiao, Di Liu, Anquan Zhu, Jinxian Feng, Pengfei Zhou, Chunfa Liu, Kar Wei Ng, Hui Pan
Summary: This study reveals that surface evolution plays a crucial role in enhancing the electrocatalytic performance of transition metal oxides for electrochemical nitrate reduction reaction (e-NO3RR). Incorporating nickel into Co3O4 can promote surface reconstruction and improve the adsorption of intermediates and reduce energy barriers, leading to enhanced catalytic performance. The reconstructed cobalt-nickel hydroxides (CoyNi1_y(OH)2) on the catalyst's surface serve as the active phase.
APPLIED CATALYSIS B-ENVIRONMENTAL
(2024)
Article
Chemistry, Physical
Zishen Wang, Jing-Yang You, Chuan Chen, Jinchao Mo, Jingyu He, Lishu Zhang, Jun Zhou, Kian Ping Loh, Yuan Ping Feng
Summary: The coexistence of charge density waves (CDWs), superconductivity, and nontrivial topology in monolayer 1H-MSe2 (M = Nb, Ta) has been observed, triggered by momentum-dependent electron-phonon coupling through electron doping. New 2 x 2 CDW phases with nontrivial topology, Dirac cones, and van Hove singularities emerge at a critical electron doping concentration. These 2 x 2 CDW phases are also found to be superconducting. This discovery provides insights into the engineering of nontrivial electronic characters and offers a platform to modulate different quantum states.
NANOSCALE HORIZONS
(2023)
Article
Chemistry, Physical
Jun Zhou, Zishen Wang, Shijie Wang, Yuan Ping Feng, Ming Yang, Lei Shen
Summary: This study reports a novel charge density wave that generates 2D ferromagnetism instead of suppressing it by forming interstitial anionic electrons as the charge modulation mechanism. This transition introduces a new magnetic form of CDWs, offering promising opportunities for exploring novel fundamental physics and advanced spintronics applications.
NANOSCALE HORIZONS
(2023)
Article
Chemistry, Physical
Mingrui Shao, Di Liu, Jinxuan Lu, Xiaofei Zhao, Jing Yu, Chao Zhang, Baoyuan Man, Hui Pan, Zhen Li
Summary: In this study, a simply-prepared and highly sensitive electric field-induced surface-enhanced Raman spectroscopy (E-SERS) substrate is proposed by combining a pyroelectric material (PMN-PT) with plasmonic silver nanoparticles (Ag NP). The SERS signals are significantly enhanced by more than 100 times after applying positive or negative pyroelectric potentials, mainly due to the chemical mechanism induced by charge transfer. Additionally, a novel nanocavity structure composed of PMN-PT/Ag/Al2O3/silver nanocubes (Ag NCs) is introduced, which can efficiently convert light energy into heat energy and achieve a tremendous enhancement of SERS signals.
NANOSCALE HORIZONS
(2023)
Review
Engineering, Environmental
Yitong Cao, Ci Sathish, Xinwei Guan, Shaobin Wang, Thava Palanisami, Ajayan Vinu, Jiabao Yi
Summary: The widespread use of plastics has resulted in severe environmental pollution with microplastics. Magnetic materials and their nanostructures have emerged as promising materials for removing and degrading microplastics. This review critically examines the recent advances in microplastic removal and degradation using magnetic materials, comparing the efficiencies of different magnetic materials and providing strategies for optimizing their performance. The review also highlights the challenges and perspectives in the development of magnetic nanomaterials for microplastic remediation.
JOURNAL OF HAZARDOUS MATERIALS
(2024)
Article
Chemistry, Multidisciplinary
Haoyun Bai, Di Liu, Hui Pan
Summary: This study demonstrates that LaOMS2 structures can be used as spin valves without contact, and shows their stability and unique magnetic and electronic properties. These structures can be applied in nanodevices and spintronics, and provide strategies for designing new devices.
MATERIALS HORIZONS
(2023)
