Cooperative Sites in Fully Exposed Pd Clusters for Low-Temperature Direct Dehydrogenation Reaction
Linlin Wang, Jiangyong Diao, Mi Peng, Yunlei Chen, Xiangbin Cai, Yuchen Deng, Fei Huang, Xuetao Qin, Dequan Xiao, Zheng Jiang, Ning Wang, Ting Sun, Xiaodong Wen, Hongyang Liu, Ding Ma
Abstract
Direct dehydrogenation of alkanes is of great interest but presents a significant challenge in activating C–H bond at a low temperature. Here, we report fully exposed Pd clusters consisting of an average of three Pd atoms on a hybrid nanodiamond-graphene support (denoted as Pd3/ND@G) for low-temperature dehydrogenation of ethylbenzene to styrene. The obtained fully exposed and atomically dispersed Pd clusters exhibit good catalytic performance (328 mmol gPd–1 h–1 ethylbenzene conversion rate and >99% styrene selectivity) and much enhanced stability under oxygen-free conditions at 350 °C, compared with the previously reported catalysts. The synergetic interaction between adjacent Pd atoms in each cluster evidenced by density functional theory (DFT) calculations guarantees effective activation of C–H bond on ethyl in ethylbenzene and easy desorption of styrene, which is the key for the higher activity than typical Pd single atom and Pd nanoparticle catalysts. The present method for precise control of fully exposed Pd clusters paves a new way for designing direct dehydrogenation catalyst at the atomic scale.