The crystal structure, phase abundance and the electrochemical properties of Zr(Mn1-x Nix)2 (0.40 ≤x≤0.75) alloys were investigated by means of XRD, Rietveld refinement method and electrochemical measurements. The a...The crystal structure, phase abundance and the electrochemical properties of Zr(Mn1-x Nix)2 (0.40 ≤x≤0.75) alloys were investigated by means of XRD, Rietveld refinement method and electrochemical measurements. The alloys are multiphase. C15 Laves phase occurs as a main phase accompanying with C14 phase and other minor phases, indicating that Ni element is C15-stabilized element for ZrMn2 alloy. The phase abundance and lattice parameters of Laves phase are influenced significantly by Ni substitution. The Zr(Mn0.45 Ni0.55)2 alloy with the highest amount of C15 phase exhibits the maximum electrochemical capacity of 242m Ah/g. C14 phase occurring in Zr-Mn-Ni alloys is beneficial for the electrochemical kinetics of hydride electrodes.展开更多
基金the National Advanced Materials Committee of China andthe National Natural Science Foundation of China(Grunt NO.5
文摘The crystal structure, phase abundance and the electrochemical properties of Zr(Mn1-x Nix)2 (0.40 ≤x≤0.75) alloys were investigated by means of XRD, Rietveld refinement method and electrochemical measurements. The alloys are multiphase. C15 Laves phase occurs as a main phase accompanying with C14 phase and other minor phases, indicating that Ni element is C15-stabilized element for ZrMn2 alloy. The phase abundance and lattice parameters of Laves phase are influenced significantly by Ni substitution. The Zr(Mn0.45 Ni0.55)2 alloy with the highest amount of C15 phase exhibits the maximum electrochemical capacity of 242m Ah/g. C14 phase occurring in Zr-Mn-Ni alloys is beneficial for the electrochemical kinetics of hydride electrodes.
基金National Natural Science Fundation of China(21006073)Shanghai Rising-Star Program(11QA1407200)+1 种基金open-project program of the State Key Laboratory of Chemical Engineering(SKL-ChE-08C07)Shanghai Leading Academic Discipline Project(B303)~~
文摘利用催化气相化学沉积(Catalytic chemical vapor deposition,CCVD)法在炭纸上原位生长得到CNF/CP复合体,并对这种复合体的物理化学性能和氧气电催化还原反应(Oxygen reduction reaction,ORR)性能进行了研究。结果表明:纳米炭纤维较为均匀地分散在炭纸上,其中纳米炭纤维具有窄的直径分布。所制CNF/CP复合体具有较大的比表面积和独特的中孔结构;相对于炭纸,CNF/CP复合体的端面碳原子和基面碳原子比例较高。另外,CNF/CP还具有较高的ORR反应活性,其ORR为2电子反应过程,原因可以归结于纳米炭纤维独特的微结构。同时,CNF/CP也具有较高的交换电流密度和较正的平衡电压。