Effects of various metal doping on the structure and catalytic activity of CoB catalyst in hydrogen production from NaBH4 hydrolysis

•Co-Sn-B, Co-Mn-B, Co-Cr-B and Co-Bi-B are prepared by chemical reduction.•The promoting effect of Sn, Mn, Cr, Bi on catalytic activity are compared.•Cr and Bi dopants exhibit a better promoting effect than Sn and Mn.•The promoting effect can be attributed to BET surface and synergistic effect.