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Journal of Advanced Ceramics 2024年第3期13卷 263-271页

作者： Xuanyu Chen Ziqi Ma Bin Li Yejing Dai School of Materials Sun Yat-sen UniversityShenzhen 518107China

In this study,(Cr_(1/3)/Ta_(2/3))non-equivalent co-doped Bi_(4)Ti_(3)O_(12)(BIT)ceramics were prepared to solve the problem that high piezoelectric performance,high Curie temperature,and high-temperature resistivity could not be achieved simultaneously in BIT-based ceramics.A series of Bi_(4)Ti_(3-x)(Cr_(1/3)Ta_(2/3))_(x)O_(12)(x=0-0.04)ceramics were synthesized by the solid-state reaction method.The phase structure,microstructure,piezoelectric performance,and conductive mechanism of the samples were systematically investigated.The B-site non-equivalent co-doping strategy combining high-valence Ta^(5+)and low-valence Cr^(3+)significantly enhances electrical properties due to a decrease in oxygen vacancy concentration.Bi_(4)Ti_(2.97)(Cr_(1/3)Ta_(2/3))_(0.03)O_(12)ceramics exhibit a high piezoelectric coefficient(d_(33)=26 pC·N^(-1))and a high Curie temperature(TC=687℃).Moreover,the significantly increased resistivity(ρ=2.8×10^(6)Ω·cm at 500℃)and good piezoelectric stability up to 600℃are also obtained for this composition.All the results demonstrate that Cr/Ta co-doped BIT-based ceramics have great potential to be applied in high-temperature piezoelectric applications.

关键词： high temperature piezoelectricity co-doped Bi_(4)Ti_(3)O_(12)(BIT)

Enhanced Photothermal Selective conversion of co_(2)to CH4 in Water Vapor over Rod-Like Cu and N co-doped TiO_(2)

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Chinese Journal of Structural Chemistry 2022年第12期41卷 33-42页

作者： Ji-Chao Wang Xiu Qiao Weina Shi Huiling Gao Lingchen Guo college of Chemistry and Chemical Engineering Henan Institute of Science and TechnologyXinxiang 453000China School of Chemistry and Materials Engineering Xinxiang UniversityXinxiang 453000China School of Ecology and Environment Zhengzhou UniversityZhengzhou 450052China

Enhancing catalytic efficiency and selectivity is critical issues for co_(2) conversion.The rod-like Cu/N co-doped TiO_(2) samples(Cu/N-TiO_(2)) were synthesized by the electrospinning-calcination method.The substitutional Cu and interstitial N doping not only enhanced visible-light absorption ability,but also formed the Ti(Ⅲ)sites.The obviously synergistic effect between the photocatalysis and thermalcatalysis appeared for co_(2) conversion over the 8-Cu/N-TiO_(2) catalyst.After 9 h visible-light-illumination at 160℃,the co,CH4and O_(2) yields reached 49.7,1455.1 and 2910.2μmol/gcat,respectively.In the 7thcycling,the yields of two main CH4and O_(2) products were slightly down by less than 11.5%,and the selectivity of CH_(4) product kept above 98%.combined with the theoretical surface mode,Cu/N co-doping could promote the adsorption-ability for H_(2)O and co_(2) molecules and reduce activation-energy for co_(2)conversion.Hence,the co-doping construction showed a great significance of designing efficient photothermal catalysts for the co_(2)conversion application.

关键词： co_(2)conversion photothermal catalysis rod-like TiO_(2) co-doped

In Situ Preparation and Analysis of Bimetal co?doped Mesoporous Graphitic Carbon Nitride with Enhanced Photocatalytic Activity

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Nano-Micro Letters 2019年第1期11卷 175-190页

作者： Wanbao Wu Zhaohui Ruan Junzhuo Li Yudong Li Yanqiu Jiang Xianzhu Xu Defeng Li Yuan Yuan Kaifeng Lin School of Chemistry and Chemical Engineering Harbin Institute of Technology Key Laboratory of Aerospace Thermophysics Ministry of Industry and Information TechnologyHarbin Institute of Technology

A novel photocatalyst of mesoporous graphitic carbon nitride(g-C_3N_4) co-doped with co and Mo(co/Mo-MCN) has been one-pot synthesized via a simple template-free method; cobalt chloride and molybdenum disulfide were used as the co and Mo sources, respectively. The characterization results evidently indicate that molybdenum disulfide functions as Mo sources to incorporate Mo atoms in the framework of g-C_3N_4 and as a catalyst for promoting the decomposition of g-C_3N_4, resulting in the creation of mesopores. The obtained co/Mo-MCN exhibited a significant enhancement of the photocatalytic activity in H_2 evolution(8.6 times) and Rhodamine B degradation(10.1 times) under visible light irradiation compared to pristine g-C_3N_4. Furthermore, density functional theory calculations were applied to further understand the photocatalytic enhancement mechanism of the optical absorption properties at the atomic level after co-or Mo-doping. Finite-di erence time-domain simulations were performed to evaluate the e ect of the mesopore structures on the light absorption capability. The results revealed that both the bimetal doping and the mesoporous architectures resulted in an enhanced optical absorption; this phenomenon was considered to have played a critical role in the improvement in the photocatalytic performance of co/Mo-MCN.

关键词： co-doped g-C3N4 Porous g-C3N4 Photocatalysis Optical simulation Light absorption intensity

Study on superstructure in ion co-doped BiFeO_3 by using transmission electron microscopy

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Chinese Physics B 2015年第4期24卷 290-295页

作者：蒲十周郭超李美亚陈珍莲邹化民 Key Laboratory of Artificial Micro- and Nano-structures of Ministry of Education and School of Physics and Technology Wuhan University Center for Electron Microscopy Wuhan University Ningbo Institute of Material Technology and Engineering Chinese Academy of Sciences

La3＋ and V5＋ co-doped BiFeO3 ceramics are synthesized by rapid liquid sintering technique. The modulated structure in Bi0.85La0.15Fe0.97V0.03O3 is investigated by using transmission electron microscopy （TEM）. Two kinds of superstructures are observed in the samples. One is the component modulated superstructure and twin-domain, which is generated by La3＋ ordered substitution for Bi3＋ and frequently appears. The chemical composition of the superstructure is explored by x-ray energy dispersive spectroscopy （EDS）. The model of the ordered structure is proposed. Simulation based on the model is conducted. The second is the fluorite-type δ-Bi2O3 related superstructure. The relation between the ferroelectric property and the microstructure of the sample is also discussed.

关键词： multiferroic materials superstructure co-doped rapid liquid sintering technique

Preparation of nitrogen and sulfur co-doped ultrathin graphitic carbon via annealing bagasse lignin as potential electrocatalyst towards oxygen reduction reaction in alkaline and acid media

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Journal of Energy Chemistry 2019年第7期28卷 33-42页

作者： Yixing Shen Feng Peng Yonghai Cao Jianliang Zuo Hongjuan Wang Hao Yu School of Chemistry and Chemical Engineering South China University of TechnologyGuangzhou 510640GuangdongChina Guangzhou Key Laboratory for New Energy and Green Catalysis School of Chemistry and Chemical EngineeringGuangzhou UniversityGuangzhou 510006GuangdongChina

Renewable lignin used for synthesizing materials has been proven to be highly potential in specific electrochemistry.Here,we report a simple method to synthesize nitrogen and sulfur co-doped carbon nanosheets by using bagasse lignin,denoted as lignin-derived carbon(LC).By adjusting the ratio of nitrogen source and annealing temperature,we obtained the ultrathin graphitic lignin carbon(LC-4-1000)with abundant wrinkles with high surface area of 1208 m2g_1 and large pore volume of 1.40 cm3g_1.In alkaline medium,LC-4-1000 has more positive half-wave potential and nearly current density compared to commercial Pt/C for oxygen reduction reaction(ORR).More importantly,LC-4-1000 also exhibits comparable activity and superior stability for ORR in acid medium due to its high graphitic N ratio and a direct four electron pathway for ORR.This study develops a cost-effective and highly efficient method to prepare biocarbon catalyst for ORR in fuel cells.

关键词： Electrocatalyst Biocarbon Lignin Nitrogen and sulfur co-doped carbon Oxygen reduction reaction

Study on positive temperature coefficient of resistivity of co-doped BaTiO_3 with Curie temperature in room temperature region

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Science China(Technological Sciences) 2019年第5期62卷 811-819页

作者： YU AiMei LI Qiang FAN DeSong ZHANG HongLiang MIIT Key Laboratory of Thermal control of Electronic Equipment School of Energy and Power EngineeringNanjing University of Science & Technology

As a temperature self-regulating heater material, the doped BaTiO_3 exhibits an attractive application perspective in the thermal management of electrical devices. However, the high Curie temperature does not meet the requirement in the thermal control application. In this work,(Ba_(0.997-x)Ce_(0.003)Sr_x)(TiNb_(0.002))O_3(x=0.2, 0.3, 0.35, abbreviated as BCSTNs) ceramics were prepared by the solid-state reaction method. The purpose of doping different content of strontium is to shift the Curie temperature of BaTiO_3-based ceramic to the ambient temperature region, maintaining excellent PT_C effect and low room-temperature resistivity by codoped cation ions in Ba-and Ti-site. The influences of sintering temperature and soak time on the microstructure as well as electrical properties of BCSTNs ceramics have been studied. The X-ray diffraction reveals that the composition with x=0.35 exhibits the coexistence of tetragonal and cubic lattice symmetries, confirmed by the Rietveld structure refinement. The dense microstructure with average grain sizes 0.84–7.87 μm was observed for BCSTN ceramics. Temperature-resistivity measurements demonstrate that T_C of the ceramics with x=0.35 shifted to the room temperature region. Additionally, the BCSTN ceramic with heavy doping Sr exhibits relative low room-temperature resistivity and the resistance jump greater than 2.0 orders of magnitude.

关键词： electrical heating co-doped BaTiO3 curie temperature positive temperature coefficient of resistivity

Structure, photocatalytic and antibacterial activity study of Meso porous Ni and S co-doped TiO2 nano material under visible light irradiation

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Chinese Journal of Chemical Engineering 2019年第7期27卷 1630-1641页

作者： K.V.Divya Lakshmi T.Siva Rao J.Swathi Padmaja I.Manga Raju M.Ravi Kumar Department of Inorganic and Analytical Chemistry Andhra University

Undoped and Ni–S co-doped mesoporous TiO2 nano materials were synthesized by using sol–gel method.The characteristic features of as prepared catalyst samples were investigated using various advanced spectroscopic and analytical techniques.The characterization results of the samples revealed that all the samples exhibited anatase phase(XRD),decreasing band gap(2.68 eV)(UV–Vis-DRS),small particle size(9.2 nm)(TEM),high surface area(142.156 m^2·g^-1)(BET),particles with spherical shape and smooth morphology(SEM);there is a frequency shift observed for co-doped sample(FT-IR)and the elemental composition electronic states and position of the doped elements(Ni and S)in the TiO2 lattice analyzed by XPS and EDX.These results supported the photocatalytic degradation of Bismarck Brown Red(BBR)achieved with in 110 min and also exhibited the antibacterial activity on Staphylococcus aureus(MTCC-3160),Pseudomonas fluorescence(MTCC-1688)under visible light irradiation.

关键词： Sol–gel Ni–S co-doped TiO2 Photocatalysis under visible light Degradation of Bismarck Brown Red Antibacterial activity

Structural, ferromagnetic, and optical properties of Fe and Al co-doped ZnO diluted magnetic semiconductor nanoparticles synthesized under high magnetic field

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Advances in Manufacturing 2019年第2期7卷 248-255页

作者： Muhammad Tariq Ying Li Wen-Xian Li Zhong-Rui Yu Jia-Mei Li Ye-Min Hu Ming-Yuan Zhu Hong-Ming Jin Yang Liu Yi-Bing Li Katerina Skotnicova School of Materials Science and Engineering/Institute for Sustainable Energy/Institute of Mateirals Shanghai University Shanghai 20072 People's Republic of China School of Chemistry The University of New South Wales Sydney NSW 2052 Australia Faculty of Metallurgy and Materials Engineering VSB-Technical University of Ostrava Ostrava Czech Republic

In this study, 2% Fe and 3% Al co-doped ZnO nanoparticles were synthesized using a hydrothermal method under high magnetic field (HMF). The influences of HMF on the structural, optical, and ferromagnetic properties of Fe and Al co-doped ZnO nanoparticles were characterized and analyzed. The single-phase wurtzite structure of the synthesized samples was confirmed using X-ray diffraction (XRD), high-resolution transmission electron microscopy (HRTEM), and Raman spectroscopy analysis. The application of HMF decreases the particle size of the spherical nanocrystal as observed by scanning electron microscopy (SEM). Optical analysis indicated that the absoqjtion edge shifted towards a higher wavelength (red shift). The nanoparticles synthesized under the HMF exhibited high room temperature ferromagnetism (RTFM) performance because of the high oxygen vacancy (VO) content as revealed by X-ray photoelectron spectroscopy (XPS), which was in agreement with the prediction of the bound magnetic polarons theory.

关键词： Fe and Al co-doped ZnO nanoparticles Room temperature ferromagnetism (RTFM) High magnetic field Hydrothermal Optical property

Photocatalytic degradation of coking wastewater by nanocrystalline (Fe,N) co-doped TiO_2 powders

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中国科学：技术科学英文版 2010年第6期53卷 1477-1482页

作者： LIU WenXiu1,LIU Qing1,LI XiuFang1,2,SONG YunTing1 & CAO WenBin1 1 Department of Inorganic Nonmetallic Materials,School of Materials Science and Engineering,University of Science and Technology Beijing,Beijing 100083,China 2 Tangshan Iron & Steel co.,Ltd,Tangshan 063016,China Department of Inorganic Nonmetallic Materials School of Materials Science and Engineering University of Science and Technology Beijing Beijing China Tangshan Iron & Steel co. Ltd Tangshan China

The yellowish nitrogen and iron co-doped nanocrystalline titanium dioxide ((Fe,N) co-doped TiO2) powders have been prepared by hydrothermal method using TiOSO4 and co(NH2)2 as starting materials.The grain size of the synthesized powders was estimated as 11 nm by Scherrer's method.The UV-Vis diffuse reflectance spectra indicated that the light absorption edge of the powders was red-shifted up to 605 nm.And the doped TiO2 powders exhibited good photocatalytic activities during the photo-degradation of coking wastewater under sunshine irradiation.The biotreatability of the coking wasterwater after photocatalytic degradation was improved greatly and it is more suitable to be further treated by biochemical method.

关键词： (Fe N) co-doped TiO2 photo-degradation coking wastewater

Physical mechanism of resistance switching in the co-doped RRAM

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Journal of Semiconductors 2017年第1期38卷 100-105页

作者： Jin Yang Yuehua Dai Shibin Lu Xianwei Jiang Feifei Wang Junning Chen Department of Research Hefei Normal University School of Electronics and Information Engineering Anhui University

The physical mechanism of the resistance switching for RRAM with co-doped defects（Ag and oxygen vacancy）is studied based on the first principle calculations and the simulation tool VASR The interaction energy,formation energy and density of states of Ag and oxygen vacancy defect（VO）are calculated.The calculated results reveal that the co-doped system is more stable than the system only doped either Ag or VO defect and the impurity energy levels in the band gap are contributed by Ag and VO defects.The obtained partial charge density confirmed further that the clusters are obvious in the direction of Ag to Hf ions,which means that it is Ag but VO plays a role of conductive paths.For the formation mechanism,the modified electron affinity and the partial charge density difference are calculated.The results show that the ability of electron donors of Ag is stronger than VO In conclusion,the conductivity of the physical mechanism of resistance switching in the co-doped system mainly depends on the doped Ag.

关键词： RRAM resistive switching co-doped conductive path physical mechanism