非晶态合金Ni-Fe-B的制备及其催化活性

Preparation and Catalytic Activity of Amorphous Alloy Ni-Fe-B

采用液相还原法合成了一系列非晶态合金Ni-Fe-B,考察了铁物质的量比、反应温度和表面活性剂对非晶态合金Ni-Fe-B的物相、形貌以及催化活性的影响。借助X射线粉末衍射、透射电镜对产物进行了表征分析。以NaBH4的催化水解制氢作为探针反应,对所得非晶态合金Ni-Fe-B的催化活性进行了评价。研究结果表明:所得产物Ni-Fe-B具有相对稳定的非晶态物相结构,铁物质的量比的升高,促使产物向晶态化转变。当铁物质的量比为0.5,反应温度为333 K时,所得Ni-Fe-B的催化活性最高,产氢速率可达1.70 mL/min。非离子型表面活性剂辅助所得非晶态产物的粒径小、分散度最高,催化活性进一步增强,产氢速率可提高到1.98mL/min。

A series of amorphous alloy Ni-Fe-B catalysts were synthesized by using liquid phase reduction method. The influences of reaction conditions,such as n( Fe) /n( Fe + Ni) molar ratios,temperature and the type of surfactants,on phase morphology and catalytic activity were investigated. The as-obtained product samples were characterized and analyzed by using X-ray powder diffraction( XRD) and transmission electron microscope(TEM). The catalytic activities of the related samples were evaluated by the hydrolysis of sodium borohydride solution. The results show that the products have stable amorphous phase structures. With the rise of n( Fe) /n( Fe + Ni),the crystallization tendency rises and the agglomeration strengthens. Under the conditions(T = 333 K,n( Fe) /n( Fe + Ni) = 0. 5),the as-prepared samples exhibit higher catalytic activity than others,and the highest hydrogen production rate is 1. 70 mL /min. The sample obtained with assistance of non-ionic surfactant possesses highest catalytic activity,and the hydrogen production rate is 1. 98 mL /min.