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Journal of Advanced Ceramics 2024年第2期13卷 135-142页

作者： Yudi Qiu Shunjian Xu Xiangzhao Zhang Mingfen Zhang Qinhan Guo Beiji Wang guanjun qiao Guiwu Liu School of Materials Science and Engineering Jiangsu UniversityZhenjiang 212013China School of Intelligent Manufacturing Huzhou CollegeHuzhou 313000China

We firstly performed the reactive air wetting and brazing of Al_(2)O_(3) ceramics using Ag-(0.5-12)Nb_(2)O_(5) fillers,where Nb_(2)O_(5) can react with liquid Ag and O2 from air to generate AgNbO_(3).The contact angle of the Ag-Nb_(2)O_(5)/Al_(2)O_(3) system almost linearly decreases from~71.6°to 32.5°with the Nb_(2)O_(5) content increasing,and the joint shear strength reaches the maximum of~65.1 MPa while employing the Ag-4Nb_(2)O_(5) filler,which are mainly related to the formation and distribution of the AgNbO_(3) phase at the ***,the interfacial bonding and electronic properties of related interfaces were investigated by first-principles *** calculated works of adhesion(Wa)of Ag(111)/Ag-O-AgNbO_(3)(001)and AgNbO_(3)(001)/Al_(2)O_(3)(100)interfaces are higher than that of the Ag(111)/Al_(2)O_(3)(110)interface,indicating good reliability of the Ag/AgNbO_(3)/Al_(2)O_(3) *** relatively large interfacial charge transfer indicates the formation of Ag-Ag,Al-O,and Ag-O bonds in the Ag/AgNbO_(3)/Al_(2)O_(3) structure,which can contribute to the interfacial bonding.

关键词： reactive air brazing(RAB) wettability microstructure shear strength first-principles calculations

Revisiting traditional and modern trends in versatile 2D nanomaterials: Synthetic strategies, structural stability, and gas-sensing fundamentals

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Journal of Advanced Ceramics 2023年第12期12卷 2149-2246页

作者： Mobashar Hassan Siwei Liu Zhiping Liang Shahid Hussain Junlin Liu Guiwu Liu guanjun qiao School of Materials Science and Engineering Jiangsu UniversityZhenjiang 212013China

Two-dimensional nanomaterials(2DNMs)have attracted significant research interest due to their outstanding structural properties,which include unique electrical nanostructures,large surface areas,and high surface *** adaptable materials have outstanding physicochemical characteristics,making them useful in a variety of applications such as gas-sensing,electronics,energy storage,and *** research has been conducted in the pursuit of high performance room-temperature(RT)gas sensors with good selectivity,high sensitivity,long-term stability,and rapid response/recovery *** oxides,transition metal chalcogenides,MXenes,graphene,phosphorene,and boron nitride have all been discovered as 2DNMs with strong potential for gas *** review presents an in-depth analysis of current advances in 2DNM *** includes synthetic techniques,structural stabilities,gas-sensing mechanisms,critical performance parameters,and factors influencing gas-sensing capabilities of ***,the present study emphasizes structural engineering and optimization methodologies that improve gas-sensing *** also highlights current challenges and outlines future research directions in the domain of tailoring 2DNMs for advanced RT gas *** systematically designed comprehensive review article aims to provide readers with profound insights into gas detection,thereby inspiring the generation of innovative ideas to develop cutting-edge 2DNMs-based gas sensors.

关键词： 2D nanomaterials synthetic strategies structural stability gas-sensing mechanism

Efficient photocatalytic hydrogen evolution coupled with benzaldehyde production over 0D Cd_(0.5)Zn_(0.5)S/2D Ti_(3)C2 Schottky heterojunction

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Journal of Advanced Ceramics 2022年第7期11卷 1117-1130页

作者： Junnan TAO Mingyuan WANG Guiwu LIU Qinqin LIU Lei LU Neng WAN Hua TANG guanjun qiao School of Materials Science and Engineering Jiangsu UniversityZhenjiang 212013China SEU-FEI Nano-Pico Center Key Laboratory of MEMS of Ministry of EducationSchool of Electrical Science and EngineeringSoutheast UniversityNanjing 210096China School of Environmental Science and Engineering Qingdao UniversityQingdao 266071China

Converting water into hydrogen fuel and oxidizing benzyl alcohol to benzaldehyde simultaneously under visible light illumination is of great significance,but the fast recombination of photogenerated carriers in photocatalysts seriously decreases the conversion ***,a novel dual-functional 0D Cd_(0.5)Zn_(0.5)S/2D Ti_(3)C2 hybrid was fabricated by a solvothermally in-situ generated assembling *** Cd_(0.5)Zn_(0.5)S nano-spheres with a fluffy surface completely and uniformly covered the ultrathin Ti_(3)C2 nanosheets,leading to the increased Schottky barrier(SB)sites due to a large contact area,which could accelerate the electron–hole separation and improve the light *** optimized Cd_(0.5)Zn_(0.5)S/Ti_(3)C2 hybrid simultaneously presents a hydrogen evolution rate of 5.3 mmol/(g·h)and a benzaldehyde production rate of 29.3 mmol/(g·h),which are~3.2 and 2 times higher than those of pristine Cd_(0.5)Zn_(0.5)S,*** the multiple experimental measurements and the density functional theory(DFT)calculations further demonstrate the tight connection between Cd_(0.5)Zn_(0.5)S and Ti_(3)C2,formation of Schottky junction,and efficient photogenerated electron–hole *** paper suggests a dual-functional composite catalyst for photocatalytic hydrogen evolution and benzaldehyde production,and provides a new strategy for preventing the photogenerated electrons and holes from recombining by constructing a 0D/2D heterojunction with increased SB sites.

关键词： Cd_(0.5)Zn_(0.5)S Ti_(3)C2 photocatalysis hydrogen benzaldehyde Schottky heterojunction

Electrospun Cu-doped In_(2)O_(3) hollow nanofibers with enhanced H2S gas sensing performance

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Journal of Advanced Ceramics 2022年第3期11卷 427-442页

作者： Yu ZHANG Shuai HAN Mingyuan WANG Siwei LIU Guiwu LIU Xianfeng MENG Ziwei XU Mingsong WANG guanjun qiao School of Materials Science and Engineering Jiangsu UniversityZhenjiang 212013China SEU-FEI Nano-Pico Center Key Laboratory of MEMS of Ministry of EducationSchool of Electrical Science and EngineeringSoutheast UniversityNanjing 210096China

One-dimensional nanofibers can be transformed into hollow structures with larger specific surface area, which contributes to the enhancement of gas adsorption. We firstly fabricated Cu-doped In_(2)O_(3) (Cu-In_(2)O_(3)) hollow nanofibers by electrospinning and calcination for detecting H2S. The experimental results show that the Cu doping concentration besides the operating temperature, gas concentration, and relative humidity can greatly affect the H2S sensing performance of the In_(2)O_(3)-based sensors. In particular, the responses of 6%Cu-In_(2)O_(3) hollow nanofibers are 350.7 and 4201.5 to 50 and 100 ppm H2S at 250 ℃, which are over 20 and 140 times higher than those of pristine In_(2)O_(3) hollow nanofibers, respectively. Moreover, the corresponding sensor exhibits excellent selectivity and good reproducibility towards H2S, and the response of 6%Cu-In_(2)O_(3) is still 1.5 to 1 ppm H2S. Finally, the gas sensing mechanism of Cu-In_(2)O_(3) hollow nanofibers is thoroughly discussed, along with the assistance of first-principles calculations. Both the formation of hollow structure and Cu doping contribute to provide more active sites, and meanwhile a little CuO can form p–n heterojunctions with In_(2)O_(3) and react with H2S, resulting in significant improvement of gas sensing performance. The Cu-In_(2)O_(3) hollow nanofibers can be tailored for practical application to selectively detect H2S at lower concentrations.

关键词： electrospinning Cu-doped In_(2)O_(3) hollow nanofibers H2S detection

Enhanced figure of merit for famatinite Cu_(3)SbSe_(4)via band structure tuning and hierarchical architecture

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Journal of Materiomics 2023年第6期9卷 1263-1272页

作者： Lijun Zhao Haolin Ye Xinmeng Wu Jian Yang Lihua Yu Zhongqi Shi Shahid Hussain guanjun qiao Junhua Xu Bangzhi Ge Li Wang Chongjian Zhou School of Materials Science and Engineering Jiangsu University of Science and TechnologyZhenjiang212100JiangsuChina State Key Laboratory of Solidification Processing Key Laboratory of Radiation Detection Materials and DevicesMinistry of Industry and Information TechnologyNorthwestern Polytechnical UniversityXi'an710072ShaanxiChina School of Materials Science and Engineering Jiangsu UniversityZhenjiang212013JiangsuChina State Key Laboratory for Mechanical Behavior of Materials Xi'an Jiaotong UniversityXi'an710049ShaanxiChina

The p-type Te-free Cu_(3)SbSe_(4)with famatinite structure is a potential candidate for thermoelectric materials due to the low cost and eco-friendly constituent ***,its strong bipolar effect and high lattice thermal conductivity(klat)are the main challenges for its performance ***,we report a new strategy to enhance its figure of merit zT~0.86 at 673 K for Cu_(3)Sb_(0.95)Fe_(0.05)Se_(2.8)S_(1.2)via band structure tuning and hierarchical ***,S substituted Se atoms in lattice can widen the band gap to alleviate the bipolar ***,Fe doping in Sb site significantly increases the density of states,thus increasing the carrier effective mass,and obtaining a remarkably high Seebeck coefficient of~560 mV/K at 300 ***,the induced hierarchical architecture defects resulting in a minimum klat of~0.48 W·m^(-1)·K^(-1)at 673 ***,the improved Seebeck coefficient combined with low thermal conductivity leads to an enhanced zT.

关键词： Cu3SbSe4-Based materials Defects Band gap Thermoelectric properties Solid solution

High energy density in ultra-thick and flexible electrodes enabled by designed conductive agent/binder composite

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Journal of Energy Chemistry 2024年第3期90卷 133-143,I0005页

作者： Xiaoyu Shen Hailong Yu Liubin Ben Wenwu Zhao Qiyu Wang guanjun Cen Ronghan qiao Yida Wu Xuejie Huang Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China Songshan Lake Materials Laboratory Dongguan 523808Guangdong China

Thick electrodes can increase incorporation of active electrode materials by diminishing the proportion of inactive constituents,improving the overall energy density of ***,thick electrodes fabricated using the conventional slurry casting approach frequently exhibit an exacerbated accumulation of carbon additives and binders on their surfaces,invariably leading to compromised electrochemical *** this study,we introduce a designed conductive agent/binder composite synthesized from carbon nanotube and *** agent/binder composite facilitates production of dry-process-prepared ultra-thick electrodes endowed with a three-dimensional and uniformly distributed percolative architecture,ensuring superior electronic conductivity and remarkable mechanical *** this approach,ultra-thick LiCoO_(2)(LCO) electrodes demonstrated superior cycling performance and rate capabilities,registering an impressive loading capacity of up to 101.4 mg/cm^(2),signifying a 242% increase in battery energy *** another analytical endeavor,time-of-flight secondary ion mass spectroscopy was used to clarify the distribution of cathode electrolyte interphase(CEI) in cycled LCO *** results provide unprecedented evidence explaining the intricate correlation between CEI generation and carbon distribution,highlighting the intrinsic advantages of the proposed dry-process approach in fine-tu ning the CEI,with excellent cycling performance in batteries equipped with ultra-thick electrodes.

关键词： Conductive agent/binder composite Dry process Ultra-thick electrodes High energy density CEI reconstruction ToF-SIMS

Microstructure and properties of Si_3N_4 ceramics obtained from addition of β-phase seeds and celsian

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Journal of University of Science and Technology Beijing 2006年第5期13卷 465-468页

作者： Jun Yang Jiqiang Gao Jianfeng Yang guanjun qiao Yonghong Luo State Key Laboratory for Mechanical Behavior of Materials Xi＇an Jiaotong University Xi＇an 710049 China Xi＇an University of Architecture and Technology Xi＇an 710055 China

The silicon nitride based ceramics obtained by the addition of β-Si3N4 seeds was fabricated using celsian as the additive and by pressureless sintering. The microstructure of the material was observed and analyzed using XRD, SEM, and TEM and the mechanical response of this array microstructure was characterized for flexural strength and fracture behavior. The result shows that the growth of the larger aspect ratio grains initiate mainly from the seeds through the heterogeneous nucleation mechanism during the process of phase transformation, and the intergranular phase BaAl2Si20s services as good refractory materials. In contrast to conventional processing, a stable bimodal microstructure and complicated component with a lower cost can be achieved using the abovementioned process theoretically and practically.

关键词： silicon nitride ceramics celsian β-silicon nitride seed pressureless sintering microstructure properties

Brazing of WC–8Co cemented carbide to steel using Cu–Ni–Al alloys as filler metal: Microstructures and joint mechanical behavior

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Journal of Materials Science & Technology 2018年第7期34卷 1180-1188页

作者： Xiangzhao Zhang Guiwu Liu Junnan Tao Yajie Guo Jingjing Wang guanjun qiao School of Materials Science and Engineering Jiangsu University Engineering Research Center of Transportation Materials of Ministry of Education School of Materials Science and Engineering Chang'an University School of Materials Science and Engineering Shanghai University State Key Laboratory for Mechanical Behavior of Materials Xi'an Jiaotong University

Three novel Cu-Ni-A1 brazing filler alloys with Cu/Ni weight ratio of 4：1 and 2.5-10 wt% Al were developed and characterized, and the wetting of three Cu-Ni-Al alloys on WC-8Co cemented carbide were investigated at 1190-1210 ℃ by the sessile drop technique. Vacuum brazing of the WC-8Co cemented carbide to SAE1045 steel using the three Cu-Ni-Al alloys as filler metal was further carried out based on the wetting test results. The interfacial interactions and joint mechanical behaviors involving microhardness, shear strength and fracture were analyzed and discussed. The experimental results show that all the three wetting systems present excellent wettability with final contact angles of less than 5 °and fast spreading. An obvious degeneration layer with continuous thin strip forms in the cemented carbide adjacent to the Cu-Ni-A1/WC-8Co interface. The variation of microhardness in the joint cross-section is closely related to the interactions （such as diffusion and solid solution） of WC-8Co/Cu-Ni-Al/steel sys- tem. Compared with the other two brazed joints, the WC-8Co/Cu-19Ni-SAl/steel brazed joint presents more reliable interlayer microstructure and mechanical property while brazing at the corresponding wetting temperatures for 5 rain, and its average shear strength is over 200 MPa after further optimizing the brazing temperature and holding time. The joint shear fracture path passes along the degeneration layer, Cu-Ni-A1/WC-8Co interface and brazing interlayer, showing a mixed ductile-brittle fracture.2018 Published by Elsevier Ltd on behalf of The editorial office of Journal of Materials Science ＆ Technology.

关键词： Cu-Ni-Al alloy Cemented carbide Brazing Microstructures Mechanical properties

Fabrication of silicon nitride/ boron nitride nanocomposite powder

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Chinese Science Bulletin 2003年第5期48卷 430-433页

作者： WANG Xiangdong qiao guanjun Kusunose Takafumi JIN Zhihao State Key Laboratory for Mechanical Behavior of Materials Xi'an Jiaotong University Xi'an 710049China Institute of Science and Industry Research (ISIR) Osaka UniversityOsaka 5670047 Japan

Si3N4/BN nanocomposite powders with the mi-crostructure of the micro-sized a-Si3N4 particles coated with nano-sized BN particles were synthesized via the chemical reaction of boric acid, urea, and a-Si3N4 powder in a hydro-gen gas. The results of XRD, TEM, and selected area elec-tron diffraction showed that amorphous BN and a little amount of turbostratic BN(t-BN) were coated on Si3N4 parti-cles as the second phase after reaction at 1100℃. After re-heating the composite powders at 1450℃ in a nitrogen gas, the amorphous and turbostratic BN is transformed into h-BN. These nanocomposite powders can be used to prepare Si3N4/BN ceramic composites by hot-pressing at 1800℃, which have perfect machinability and can be drilled with normal metal tools.

关键词：氮化硅氮化硼复合物粉末显微结构机械加工性半导体

Molecular dynamics simulation of graphene sinking during chemical vapor deposition growth on semi-molten Cu substrate

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npj Computational Materials 2020年第1期6卷 1548-1557页

作者： Ziwei Xu Guanghui Zhao Lu Qiu Xiuyun Zhang guanjun qiao Feng Ding School of Materials Science and Engineering Jiangsu UniversityZhenjiang 212013China Centre for Multidimensional Carbon Materials Institute for Basic ScienceUlsan 44919Korea School of Materials Science and Engineering Ulsan National Institute of Science and Technology(UNIST)Ulsan 44919Korea College of Physics Science and Technology Yangzhou UniversityYangzhou 225002China

Copper foil is the most promising catalyst for the synthesis of large-area,high-quality monolayer ***,it has been found that the Cu substrate is semi-molten at graphene growth *** this study,based on a self-developed C–Cu empirical potential and density functional theory(DFT)methods,we performed systematic molecular dynamics simulations to explore the stability of graphene nanostructures,i.e.,carbon nanoclusters and graphene nanoribbons,on semi-molten Cu substrates.

关键词： dynamics semi monolayer