摘要
Clean Pt nanoclusters with a diameter of1.0-2.4 nm,supported on reduced graphene oxide(rGO)nanosheets,were successfully synthesized by simple in situ thermolysis of a Pt-carbonyl complex.The supported Pt nanoclusters are in an electron-deficient state because of the electron transfer between the nanoclusters and the rGO sheets.The as-prepared Pt-1 nm/rGO shows high catalytic activity for the 100%selective hydrogenation of nitrobenzene,with the turnover frequency(TOF) reaching 975.4 h^(-1)at 25℃ and 1 atm.This number is higher than the previously reported value for the heterogeneously catalyzed hydrogenation of nitrobenzene.The proposed process follows a direct hydrogenation mechanism,as is revealed by the analyses of the intermediate products.This work presents a facile and effective synthetic approach for achieving highly efficient nanocatalysts,and can be extended to obtain other metal catalysts with ultra-small sizes and excellent performance.
本文以羰基铂为前驱体,采用简便的原位热解方法,成功地合成了负载在还原氧化石墨烯(rGO)纳米片上的直径为1.0-2.4 nm的清洁Pt纳米团簇.由于Pt纳米团簇和rGO片之间的电子转移,所制备的负载Pt纳米团簇处于缺电子状态.在25℃、1 atm下,制备的Pt纳米团簇-1 nm/rGO催化剂的硝基苯选择性加氢的转换频率(TOF)达到975.4 h^(-1).这个数值是目前硝基苯的非均相催化氢化所报道的活性最高值.此外,根据中间产物分析,Pt-1 nm/rGO催化硝基苯加氢的机理是直接氢化.这项工作在构筑高效催化剂方面提供了一个简单有效的途径,并且可以进一步扩展制备其他具有超小尺寸和卓越性能的金属催化剂.
基金
supported by the National Natural Science Foundation of China(51402362 and 21471160)
Shandong Provincial Natural Science Foundation,China(ZR2014EMQ012 and ZR2016BM12)
the Fundamental Research Funds for the Central Universities(15CX08010A,16CX05016 and 16CX05014A)
start-up fund from Tianjin University of Technology