表面Pd膜对LaNi_(4.25)Al_(0.75)合金贮氢性能的影响  

Influences of Surface Palladium Film on Hydrogen Storage Performance of LaNi_(4.25)Al_(0.75) Alloy

作　　者：刘丽飞[1] 肇博涛 张平柱[1] 叶一鸣[1] 胡石林[1] 

机构地区：[1]中国原子能科学研究院特种材料工程部,北京102413

出　　处：《中国表面工程》2015年第3期56-62,共7页China Surface Engineering

摘　　要：为改善LaNi4.25Al0.75贮氢合金表面抵抗杂质气体毒化的能力,采用化学镀对粒径d为150-300μm的LaNi4.25Al0.75颗粒进行了表面金属Pd的包覆。通过扫描电子显微镜（SEM）、能谱仪（EDS）、X射线衍射仪（XRD）对化学镀前后LaNi4.25Al0.75合金颗粒的表面形貌及结构进行表征分析;采用容量法测试材料的贮氢性能。结果表明：化学镀在LaNi4.25Al0.75颗粒表面沉积了一层晶体Pd单质,膜层均匀且有一定的致密性。表面金属Pd层能够使LaNi4.25Al0.75颗粒在含杂质（O2和N2）氢气中的贮氢容量的衰减幅度由1.928%降至0.086%,有效提升了其抵抗O2和N2毒化的能力。The LaNi4.25Al0.75 alloy particle of the size of 150-300 μm was coated with palladium via electroless plating process to improve its durability against surface poisoning by impurity gases. Surface morphologies and structure of LaNi4.25Al0.75 particles before and after electroless plating were characterized and analyzed by SEM, EDX and XRD,and the hydrogen storage properties were tested by the volumetric method. It is found that a uniform elemental Pd film of crystalline structure and certain compactness is introduced by electroless plating on the surface of LaNi4.25Al0.75 particles. The surface palladium layer is able to decrease the amplitude attenuation of hydrogen storage capacity of LaNi4.25Al0.75 particles in hydrogen with O2 and N2 impurities from 1.928% to 0.086%, and thus effectively improve its resistance against O2 and N2 impurities.

关 键 词：LaNi4.25Al0.75合金 贮氢性能 化学镀 Pd 

分 类 号：TG174.44[金属学及工艺—金属表面处理] TG139.7[金属学及工艺—金属学]