CAJ | 학술논문

采用简单的原位还原合成方法,利用具有温和还原性能的氨硼烷作为还原剂,在室温下一步还原氧化石墨烯和氯化钴混合溶液制备了还原氧化石墨烯负载钴纳米复合材料催化剂.利用所制备的钴/还原氧化石墨烯催化剂催化氨硼烷水解制氢,发现钴/还原氧化石墨烯具有优异的催化性能.相对于没有负载的钴纳米粒子以及采用硼氢化钠作为还原剂制备的钴/还原氧化石墨烯催化剂,采用氨硼烷还原制备的钴/还原氧化石墨烯催化剂表现出更加优越的催化性能.动力学测试表明,钴/还原氧化石墨烯催化氨硼烷水解反应为零级反应,同时钴/还原氧化石墨烯催化剂催化氨硼烷水解反应的活化能为27.10 kJ?mol-1,低于大部分已报道的其它催化剂,甚至一些贵金属催化剂的活化能.钴/还原氧化石墨烯催化剂有着稳定的循环使用性,特别是其具有的磁性使得它能够直接从溶液中通过磁力回收,极具应用前景.这种简单有效的合成方法有望推广到其它的金属-还原氧化石墨烯纳米复合材料体系.
채용간단적원위환원합성방법,이용구유온화환원성능적안붕완작위환원제,재실온하일보환원양화석묵희화록화고혼합용액제비료환원양화석묵희부재고납미복합재료최화제.이용소제비적고/환원양화석묵희최화제최화안붕완수해제경,발현고/환원양화석묵희구유우이적최화성능.상대우몰유부재적고납미입자이급채용붕경화납작위환원제제비적고/환원양화석묵희최화제,채용안붕완환원제비적고/환원양화석묵희최화제표현출경가우월적최화성능.동역학측시표명,고/환원양화석묵희최화안붕완수해반응위령급반응,동시고/환원양화석묵희최화제최화안붕완수해반응적활화능위27.10 kJ?mol-1,저우대부분이보도적기타최화제,심지일사귀금속최화제적활화능.고/환원양화석묵희최화제유착은정적순배사용성,특별시기구유적자성사득타능구직접종용액중통과자력회수,겁구응용전경.저충간단유효적합성방법유망추엄도기타적금속-환원양화석묵희납미복합재료체계.
Cobalt nanoparticles (NPs) supported on reduced graphene oxide (RGO) were synthesized by a one-step in situ co-reduction of an aqueous solution of cobalt(II) chloride and graphene oxide (GO) using ammonia borane (AB) as the sole reductant under ambient conditions. The as-synthesized Co/RGO catalysts exhibited high catalytic activity for the hydrolytic dehydrogenation of AB at room temperature. The as-synthesized Co/RGO nanocatalysts exhibited much higher catalytic activity than the RGO-free Co counterpart. Compared with the nanocatalysts reduced by NaBH4, the Co/RGO nanocatalysts generated by the milder reductant AB exhibited superior catalytic activity. Moreover, kinetic studies indicate that the catalytic hydrolysis of AB by Co/RGO has zero order kinetics with respect to the substrate concentration. The hydrolysis activation energy is estimated to be about 27.10 kJ?mol-1, which is lower than most reported data for the same reaction using non-noble metal catalysts and some noble metal containing catalysts. Furthermore, the RGO-supported Co NPs show good recyclability and magnetic reusability for hydrogen generation from an aqueous solution of AB, which enables the practical reuse of the catalysts. Hence, this general method indicates that AB can be used as both a potential hydrogen storage material and an efficient reducing agent, and can be easily extended to the facile preparation of other RGO-based metal ic systems.