Correlation between electrochemical properties of the CNTs/AB5 composite hydrogen storage alloys and their catalytic properties for KBH4

Abstract

Searching for non-precious metal anode catalysts with high catalytic activity and capable of inhibiting hydrolysis side reactions is very important for direct borohydride fuel cell (DBFC). In this work, the as-cast AB5 alloy powders are firstly mixed with CNTs in a ratio of 1:9. Then the mixture of AB5 alloy and CNTs is ball milled in different milling time. Finally, the CNTs/AB5 composite alloys are obtained. Not only the catalytic properties of the CNTs/AB5 composite alloys used as anode catalysts in DBFC, but also the electrochemical properties of the alloys have been investigated in detail. The research results indicate that, as the ball milling time is extended, the electrochemical properties and catalytic properties on ΒΗ4− of the CNTs/AB5 composite alloys become better first and then worsen. The CNTs/AB5 alloy milled 2 h exhibits the best electrochemical properties and catalytic properties. Furthermore, we predict that the electrochemical properties of the composite alloy are positively correlated with the catalytic properties as anode catalyst for DBFC.