硫脲作硫源制备过渡金属磷硫化物电解水析氢催化剂

Preparation of transition-metal phosphosulfide with thiourea as sulfur source and its usage as catalysts for hydrogen evolution

以过渡金属磷酸盐和硫脲混合物为前驱体,采用传统的程序升温还原方法制备了Ni_(2)P、Co_(2)P、MoP和WP等过渡金属磷化物的磷硫化物活性相。第ⅥB族的Mo和W等过渡金属的磷硫化物活性相中硫/金属比高于第Ⅷ族的Ni和Co的磷硫化物活性相。硫脲是较为理想的硫源,以其作硫源制备的磷硫化物在酸性条件下(0.5 mol/L H_(2)SO_(4))催化电解水析氢(HER)活性高于相应不含硫的过渡金属磷化物,硫的引入对Ni_(2)P催化剂的HER活性促进作用尤为显著。第ⅥB族Mo和W的磷化物及磷硫化物HER活性都高于第Ⅷ族的Ni和Co的磷化物和磷硫化物.

Phosphosulfides active phases of Ni_(2)P,Co_(2)P,MoP,and WP are prepared by means of conventional temperature-programmed reduction method with mixtures of transition-metal phosphates and thiourea as precursors.The ratios of sulfur/metal in phosphosulfides active phases based on VIB transition-metal(Mo and W)are higher than that in phosphosulfides active phases based onⅧtransition-metal(Ni and Co).Thiourea is an ideal sulfur source.Transition-metal phosphosulfides obtained with thiourea as sulfur source exhibits higher activity in hydrogen evolution reaction(HER)under acidic condition(0.5 M H_(2)SO_(4))than the corresponding transition-metal phosphides without sulfur.The promoting effect of sulfur shows more pronounced for Ni_(2)P.HER activities of VIB transition-metal(Mo and W)phosphides and phosphosulfides are higher than those ofⅧtransition-metal(Ni and Co)phosphides and phosphosulfides.