【摘要】 采用简单的水热/溶剂热法,经后续在氮气气氛中的热处理合成了三维花型Co-Ni/C双金属催化剂,它由交织炭片构成,金属纳米颗粒高度分散其中.随着Co/Ni摩尔比的增加,金属颗粒的粒径逐渐从26nm减至4nm左右.将该催化剂用于邻氯硝基苯选择性加氢制备邻氯苯胺反应,其催化活性最高为单金属催化活性的2倍.这是由于Co和Ni物种之间存在协同效应.氢气程序升温脱附结果显示,Co/Ni合金的生成使得Co50Ni50/C催化剂产生了新的催化活性位,因而其活性显著提高.更多还原

【Abstract】 Three dimensional flower-like Co-Ni/C bimetallic catalysts composed of interlaced carbon flakes with highly dispersed metal nanoparticles were synthesized by a facile hydrothermal/solvothermal process followed by a heat treatment in flowing N2.The sizes of the metal nanoparticles were from 26 to 4 nm, which became smaller as the Co/Ni molar ratio increased. The catalytic activities for the selective hydrogenation of o-chloronitrobenzene to o-chloroaniline were tested. The conversion of o-chloronitrobenzene over the bimetallic Co-Ni/C catalysts was increased by up to 200% compared with that over a mono-metallic Co/C catalyst, which was due to a synergistic interaction between the Co and Ni species. Hydrogen temperature-programmed desorption results showed that new active sites were formed in the Co50Ni50/C catalyst due to the formation of a Co-Ni alloy, which gave the improved activity of the Co50Ni50/C catalyst.更多还原