旋转静电纺丝法制备PtCo纳米纤维及其电化学性能研究

Preparation of PtCo nanofibers by rotating electrospinning method and study on electrochemical properties

为了获得具有更佳电化学性能与更持久耐用度的低成本合金催化剂,运用旋转静电纺丝法制备了铂钴合金(PtCo)纳米纤维。对金属盐(六氯铂酸、乙酸钴)及聚乙烯吡咯烷酮(PVP)溶液浓度、纺丝器旋转速度、电场强度等参数进行了优化,并借助扫描式电子显微镜(SEM)、X射线衍射仪(XRD)等分析了PtCo纳米纤维的组织与成分,确定了其最佳的制备工艺参数组合;利用循环伏安法测试了铂钴合金纳米纤维催化剂的电化学性能。结果表明,当PVP溶液质量分数为10%、酒精与去离子水质量比为1∶1、六氯铂酸与乙酸钴质量分数为2%、铂钴摩尔比为4∶1、纺丝器转速为1600 r/min、供应电压为13 kV、收集距离为12 cm、针孔孔径为0.21 mm时,制备出的PtCo合金具有最佳的纳米级纤维型态,此时纤维丝的平均直径为76 nm,偏差值为14 nm;当铂钴摩尔比为5∶1时,PtCo纳米纤维的氢气吸附能力最强,总电荷值为3.031×10^(-3)C。

In order to obtain low-cost alloy catalysts with better electrochemical performance and longer durability,platinum cobalt alloy(PtCo)nanofibers are prepared by means of the rotating electrospinning method.The concentrations of metal salt(hexachloroplatinic acid,cobalt acetate)and polyvinylpyrrolidone(PVP)solution,the spinning speed of the spinner,the intensity of electric field and other parameters for the preparation process are adjusted and optimized.The microstructure and composition of PtCo nanofibers are analyzed by means of scanning electron microscope(SEM)and X-ray diffractometer(XRD),and the electrochemical properties are tested by cyclic voltammetry.The optimal preparation process parameters are determined.Experimental results show that the prepared PtCo alloy has the best nanoscale fiber morphology when the mass concentration of PVP solution is 10%,the mass ratio of alcohol to deionized water is 1∶1,the mass percentage of hexachloroplatinic acid to cobalt acetate is 2%,and the molar ratio of platinum to cobalt is 4∶1,the spinning speed is 1600 rpm,the supply voltage is 13 kV,the collection distance is 12 cm,and the pinhole diameter is 0.21 mm.The average diameter of the fiber is 76 nm,with a deviation of 14 nm.As the molar ratio of Pt to Co is 5∶1,the prepared PtCo nanofibers have the highest adsorption capacity to hydrogen,with total charge value of 3.031×10^(-3)C.