Cu@Co纳米颗粒合成及催化氨硼烷水解放氢性能

Synthesis of Cu@Co core-shell nanoparticles for the catalytic hydrolysis of ammonia borane

以Na BH4为还原剂合成了具有核壳结构的Cu@Co纳米颗粒,研究了其催化氨硼烷水解放氢性能。结果表明,Cu和Co的比例不同,Cu@Co纳米颗粒的催化活性也不同,其中Cu0.2@Co0.8的催化活性最高,室温下最大放氢速率达1364 m L min-1 g-1,活化能为59.1k J mol-1。Cu0.2@Co0.8催化氨硼烷水解反应对催化剂浓度是一级反应,对氨硼烷浓度为零级反应。Cu@Co核壳结构在催化反应中比Cu Co合金能够提供更多的反应活性位点,而且单质铜和钴之间存在的协同作用和电子效应在提高催化性能方面起着关键作用。

Non - noble metal Cu@ Co core - shell nanoparticles （NPs） containing a Cu core and a Co shell were synthesized by a facile chemical reduction method. In a,ddition, the catalytic performance for hydrolysis of ammonia borane （AB） was investigated. The results show that the catalytic activity of Cu@ Co NPs depend on the ratios of copper and cobalt. Among them, Cu0.2@ Co0.8 showed the best catalytic activity, with a high hydrogen generation rate of 1364 mL min^-1g^-1 at 298 K and the lower active energy of 59.1 kJ mol^-1. The dehydrogenation kinetic studies indicate that the hydrolysis of AB catalyzed by Cu0.2 @ Coo. s is first order with respect to the catalyst concentration, and it is zero - order with respect to the concentration of AB. Cu@ Co core shell nanoparticles provide more active sites on the surface to facilitate the catalytic reaction than CuCo alloy. Furthermore, the synergetic interaction and electronic effect between Cu and Co in Cu0.2@ Co0.8 play a critical role in the enhanced catalytic activity.