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Effect of sintering temperature on the chemical bonding,electronic structure and electrical transport properties of β-Ga_(1.9)fe_(0.1)O_(3) compounds

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Journal of Materials Science & Technology 2021年第8期67卷 135-144页

作者： Swadipta Roy C.V.Ramana Center for Advanced Materials Research(CMR) University of Texas at El PasoEl Paso500 W University AveEl PasoTX79968United States

A model system,which is based on iron(fe)doped gallium oxide(Ga_(2)O_(3))(Ga_(1.9)fe_(0.1)O_(3)),has been considered to elucidate the combined effect of transition-metal ion doping and processing temperature on the chemistry,local structure and chemical bonding,and electrical transport properties of a wide band gap oxide(Ga_(2)O_(3)).The Ga_(1.9)fe_(0.1)O_(3) compounds were synthesized using standard high-temperature solid state reaction *** effect of processing conditions in terms of different calcination and sintering environments on the structural and electrical properties of Ga_(1.9)fe_(0.1)O_(3) compounds is studied in *** characterization by Raman spectroscopy revealed that Ga_(1.9)fe_(0.1)O_(3) compounds exhibit monoclinic crystal symmetry,which is quite similar to the intrinsic parental crystal structure,though fedoping induces lattice *** temperature(T_(sint))which was varied in the range of 900-1200℃,has significant impact on the structure,chemical bonding,and electrical properties of Ga_(1.9)fe_(0.1)O_(3) *** spectroscopic measurements indicate the proper densification of the Ga_(1.9)fe_(0.1)O_(3) compounds achieved through complete fe diffusion into the parent Ga_(2)O_(3) lattice which is evident at the highest sintering *** X-ray photoelectron spectroscopy validates the chemical states of the constituent elements in Ga_(1.9)fe_(0.1)O_(3) *** electrical properties of Ga_(1.9)fe_(0.1)O_(3) fully controlled by T_(sint),which governed the grain size and microstructural *** temperature and frequency dependent electrical measurements demonstrated the salient features of the fe doped Ga_(2)O_(3) *** activation energy determined from Arrhenius equation is 0.5 e *** results demonstrate that control over structure,morphology,chemistry and electrical properties of the Ga_(1.9)fe_(0.1)O_(3) compounds can be achieved by optimizing T_(sint).

关键词： Ga_(2)O_(3)compounds fe-doping Raman spectroscopy Chemical bonding Electrical properties

Efficient removal of tetracycline hydrochloride through novel fe/BiOBr/Bi_(2)WO_(6) photocatalyst prepared by dual-strategy under visible-light irradiation

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Journal of Environmental Sciences 2024年第4期138卷 46-61页

作者： Guanlong Yu Kai Yang Yi Yang Yifu Li Qifang Sun Peiyuan Li Wenming Wang fengming Song Tao Ling Xuejun Peng Zhi Yu Shiquan Sun School of Hydraulic and Environmental Engineering Changsha University of Science&TechnologyChangsha 410114China Key Laboratory of Dongting Lake Aquatic Eco-Environmental Control and Restoration of Hunan Province Changsha 410114China Hunan Pilot Yanghu Reclaimed Water Co. Ltd.Changsha 410208China China Railway Wuju Group the First Engineering Co. Ltd.Changsha 410117China

It is important to investigate whether combining two modification strategies has a synergistic effect on the activity of *** this manuscript,fe-doped BiOBr/Bi_(2)WO_(6) heterojunctions were synthesized by a one-pot solvothermal method,and excellent photocatalytic performance was obtained for the degradation of tetracycline hydrochloride(TCH)in water without the addition of *** experiments and characterization,the synergistic effect between fe ion doping and the BiOBr/Bi_(2)WO_(6) heterojunction was *** fe/BiOBr/Bi_(2)WO_(6) composite photocatalyst had a beneficial void structure,enhanced visible light response,and could inhibit the recombination of photogenerated support well,which improved the photocatalytic *** presented experiments demonstrate that fe/BiOBr/Bi_(2)WO_(6) removes 97% of TCH from aqueous solution,while pure BiOBr and Bi_(2)WO_(6) only remove 56% and 65% of TCH,***,the separation and transfer mechanisms of photoexcited carriers were determined in conjunction with the experimental *** study provides a new direction for the design of efficient photocatalysts through the use of a dual co-modification strategy.

关键词： BiOBr/Bi_(2)WO_(6) fe-doping Dual strategy Tetracycline hydrochloride Photodegradation

Oxygen defects in fe-substituted Tl-system superconductors

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Science China(Technological Sciences) 1996年第1期39卷 76-83页

作者：李阳曹国辉王耘波马庆珠熊小涛陈宁马如璋郭应焕许祝安王劲松张小俊焦正宽彭获田周思海 Department of Materials Physice University of Science and Technology BeijngBeijng 100083 National Laboratory for Superconductivity Chinese Academy of SciencesBeijng 100080China National Laboratory for Superconductivity Chinese Academy of Beijing 100080 China International Center for Materials Physics Chinese Academy of SciencesShenyang 110015China National Laboratory of Nuclear Technology Chinese Academy of SciencesBeijing 100080China Department of Physics Zhejiang UniversityHangzhou 310027China Changsha Research Institute of Mining and Metallurgy Changsha 410012China

For fe-doped T1-1223 phase,the excess oxygen defects induced by fe dopants are studied by means of Hall coefficient,thermogravimetric measurements,Mossbauer spectroscopy,and the model calculation of the effective bond *** extra oxygen defects have effects on carrier density and microstructure of the *** the light doping level of fe (x=0-0.05),the superconducting transition and carrier density have significant corresponding relation--the zero resistance temperature Tco and carrier densities decrease linearly with fe dopants *** thermogravimetric measurements show that the fe3+ ions' substituting for Cu2+ ions can bring the extra oxygen into the lattice to form extra oxygen *** calculation of the effective bond valence shows that the decrease of carrier density originates the strongly localized binding of the extra oxygen *** distortion of Cu-O layer induced by the extra oxygen defects decreases the superconductive transition *** microstructures of the extra oxygen defects including the oxygen occupying and the shifts of fe and O are discussed.

关键词： Tl-system superconductors fe-doping effect extra oxygen defect carrier density.

Liquid-phase a-Pinene Isomerization over fe-doped Sulfated Zirconia Prepared by a Hydrothermal Treatment-assisted Process

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Chinese Journal of Chemistry 2011年第6期29卷 1095-1100页

作者： Liu, Jianfeng Zhao, Jie Miao, Changxi Yue, Yinghong Hua, Weiming Gao, Zi Shanghai Research Institute of Petrochemical Technology Shanghai 201208 China Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials Department of Chemistry Fudan University Shanghai 200433 China

A series of fe-doped （0.5%--3%） sulfated zirconia have been prepared by a hydrothermal treatment-assisted process. Textural and structural characterizations of the as-synthesized materials were performed by means of N2 adsorption, X-ray diffraction, transmission electron microscopy, scanning electron microscopy and thermogravimetric analysis. Temperature-programmed desorption of ammonia was used to determine the acidity of the samples. The effects of fe-doping on the structure, acidity and catalytic activity of sulfated zirconia for liquid-phase a-pinene isornerization were investigated. The incorporation of small amounts of fe into sulfated zirconia results in the increase of sulfate content and the number of acid sites, which is responsible for the enhanced activity of fe-doped catalysts in comparison with the undoped one. Meanwhile, hydrothermal treatment helps to improve the activity of the catalyst.

关键词： sulfated zirconia fe-doping hydrothermal treatment promoting effect acidity isomerization