纳米多孔型碳基铂铜合金薄膜催化剂的结构及析氢性能表征

Structure and hydrogen evolution performance of nano-porous PtCu/C membrane catalysts

采用离子束溅射(Ion Beam Sputtering,IBS)与Pt、Cu移动双靶技术,结合真空退火及酸蚀处理等后处理工艺,制备出PtCu/C薄膜催化剂。采用高分辨透射电镜(HRTEM&STEM)、原子力显微镜测试(AFM)、X射线衍射(XRD)测试薄膜催化剂的表面形貌及组织结构。通过循环伏安法(CV)和线性扫描伏安法(LSV)测试薄膜催化剂的电化学析氢性能。结果表明,经过真空退火(400℃保温1 h)及酸蚀处理(1 mol/L HNO3,50℃,120 h)后的薄膜催化剂出现类蜂窝状纳米多孔结构,其电化学析氢交换电流密度达到0.004 27 A/cm2,相较于未后处理样品的铂载量降低8.77%,催化性能提升20.62%。

PtCu / C membrane catalysts were prepared by ion beam sputtering（ IBS） with moving bimetallic Pt and Cu targets; they were post-processed by vacuum annealing in combination with acid etching. High resolution transmission electron microscopy（ HRTEM STEM） and atomic force microscope（ AFM） were employed to characterize the surface morphology of post-processed samples; the alloying degree of Pt and Cu was determined by the X-ray diffraction（ XRD）. Through cyclic voltammetry（ CV） and linear sweep voltammetry（ LSV）,the electrochemical hydrogen evolution properties of the PtCu / C membrane catalysts were investigated. The results indicated that the PtCu / C membrane catalyst annealed at 400 ℃ and etched by HNO3 exhibits honeycomb nano-porous structure; the loading of Pt is reduced by about 8.77%,whereas the catalytic activity is enhanced by about20.62%,in comparison compared with the original PtCu / C membrane catalyst.