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聚苯胺导电复合膜电化学制备及其性能 被引量:5
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作者 邓姝皓 刘星兴 +3 位作者 王彦红 王玉 吴松江 邬沛卿 《材料科学与工程学报》 CAS CSCD 北大核心 2011年第5期664-669,共6页
采用电化学氧化聚合法,以硫酸和高氯酸为掺杂剂,制备出聚苯胺(PANI)/聚乙烯醇(PVA)导电复合膜,在此复合膜上再沉积一层很薄的银层,制备出具有高导电性的复合膜。研究了苯胺聚合时间、银沉积电流密度及银沉积时间和拉伸处理对复合膜电导... 采用电化学氧化聚合法,以硫酸和高氯酸为掺杂剂,制备出聚苯胺(PANI)/聚乙烯醇(PVA)导电复合膜,在此复合膜上再沉积一层很薄的银层,制备出具有高导电性的复合膜。研究了苯胺聚合时间、银沉积电流密度及银沉积时间和拉伸处理对复合膜电导率的影响。采用扫描电镜、X射线衍射对复合膜进行表征,并对复合膜导电机理进行解析。结果表明制备的PVA-PANI复合膜电导率可达4.2S.cm-1,再经沉积薄层银后,其电导可显著提高至1136 S.cm-1。最优条件下制备的PVA-PANI复合膜为纤维状,银在此复合膜上沉积呈针状;PVA-PANI复合膜具有一定的结晶度,经拉伸后,其结晶度增大,复合膜电导得到提高,PVA-PANI复合膜具有良好力学性能。复合膜导电的基本原理是PANI与PVA互穿网络,并与银形成了三维导电网络。 展开更多
关键词 聚苯胺 复合膜 电化学制备 导电性
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Composition-controlled synthesis of platinum and palladium nanoalloys as highly active electrocatalysts for methanol oxidation 被引量:4
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作者 Haiqiang Zhao Weihong Qi +2 位作者 Xinfeng Zhou Haofei Wu Yejun Li 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2018年第2期342-349,共8页
Platinum and palladium(PtPd)alloy nanoparticles(NPs)are excellent catalysts for direct methanol fuel cells.In this study,we developed PtPd alloy NPs through the co‐reduction of K2PtCl4and Na2PdCl4in a polyol synthesi... Platinum and palladium(PtPd)alloy nanoparticles(NPs)are excellent catalysts for direct methanol fuel cells.In this study,we developed PtPd alloy NPs through the co‐reduction of K2PtCl4and Na2PdCl4in a polyol synthesis environment.During the reaction,the feed molar ratio of the two precursors was carried over to the final products,which have a narrow size distribution with a mean size of approximately4nm.The catalytic activity for methanol oxidation reactions possible depends closely on the composition of as‐prepared PtPd alloy NPs,and the NPs with a Pt atomic percentage of approximately75%result in higher activity and stability with a mass specific activity that is7times greater than that of commercial Pt/C catalysts.The results indicate that through composition control,PtPd alloy NPs can improve the effectiveness of catalytic performance. 展开更多
关键词 Platinum and palladium alloy nanoparticles Composition and size control Methanol oxidation
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Controlling atomic phosphorous-mounting surfaces of ultrafine W_(2)C nanoislands monodispersed on the carbon frameworks for enhanced hydrogen evolution 被引量:1
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作者 Xiangyong Zhang Tianying Liu +9 位作者 Ting Guo Xueying Han Zongyun Mu Qiang Chen Jiangmin Jiang Jing Yan Jiaren Yuan Dezhi Wang Zhuangzhi Wu Zongkui Kou 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2021年第10期1798-1807,共10页
Controllably mounting foreign atoms on the surfaces of earth-abundant electrocatalysts strongly improve their surface electronic properties for optimizing the catalytic performance of surficial sites to an unusual lev... Controllably mounting foreign atoms on the surfaces of earth-abundant electrocatalysts strongly improve their surface electronic properties for optimizing the catalytic performance of surficial sites to an unusual level,and provides a good platform to gain deep insights into catalytic reactions.The present work describes,employing ultrafine W2C nanoislands(average size:2.3 nm)monodispersed on the N,P dual-doped carbon frameworks as a model system,how to regulate the atomic phosphorous-mounting effect on the surfaces of W_(2)C to derive an active and stable P-mounting W_(2)C(WCP)catalyst for both acidic and alkaline hydrogen evolution reaction(HER).Since in situ phosphorus substitution into carbon sites of preformed W_(2)C nanoislands gradually proceeds from surfaces to solids,so that using a proper amount of phosphorus sources can readily control the surface mounting level to avoid the mass P-doping into the bulk.By this way,the activity per active site of WCP catalyst with robust stability can be optimized to 0.07 and 0.56 H_(2 )s^(-1) at-200 mV overpotential in acid and base,respectively,which reach up to the several-fold of pure-phase W_(2)C(0.01 and 0.05 H_(2) s^(-1)).Theoretical investigations suggest that compared with solid P doping,the P mounting on W_(2)C surface can more remarkably enhance its metallicity and decrease the hydrogen release barrier.This finding disclosed a key correlation between surface foreign atom-mounting and catalytic activity,and suggested a logical extension to other earth-abundant catalysts for various catalytic reactions. 展开更多
关键词 Tungsten carbide Doping Surficial engineering Hydrogen evolution reaction ELECTROCATALYST
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Effects of Thermal-Cold Cycling on Dimensional Stability of HIPed Beryllium
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作者 Ren Penghe Xiao Lairong +2 位作者 Cai Zhenyang Tu Xiaoxuan Zhao Xiaojun 《稀有金属材料与工程》 SCIE EI CAS CSCD 北大核心 2024年第10期2718-2722,共5页
The dimensional change,residual stress,grain orientation difference,dislocation density,and dislocation distribution of beryllium after different hot isostatic pressing treatments were analyzed by laser length meter,R... The dimensional change,residual stress,grain orientation difference,dislocation density,and dislocation distribution of beryllium after different hot isostatic pressing treatments were analyzed by laser length meter,Raman spectrometer,nanoindentation meter,electron backscattered diffractometer,and transmission electron microscope,and the influence of thermal-cold cycling treatment on the dimensional stability of beryllium was analyzed.Results show that the size of the hot isostatic pressed beryllium tends to be stable after 6 cycles of thermal-cold cycling treatment from-100℃to 150℃,and it has good dimensional stability.The dimensional stabilization mechanism of beryllium is mainly the homogenization of dislocations within the grain and the homogenization of orientation difference caused by micro-plastic deformation. 展开更多
关键词 BERYLLIUM thermal-cold cycling MICROSTRUCTURE dimensional stability
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