Noble Metal-Free 2D 1T-MoS<sub>2</sub> Edge Sites Boosting Selective Hydrogenation of Maleic Anhydride
Yi Zhao, Kuan Chang, Qingqing Gu, Bing Yang, Jing Xu, Ying Zhang, Chengsi Pan, Zhenlin Wang, Yang Lou, Yongfa Zhu
Abstract
Layered two-dimensional (2D) materials have attracted enormous attention as appealing catalysts and supports for various electro- and photocatalytic transformations. Here, we report another unique behavior of 2D MoS2 for heterogeneous selective hydrogenation, which exhibits excellent activity (100%) and selectivity (100%) for industrially important maleic anhydride (MAH) hydrogenation to succinic anhydride (SA), comparable to the cutting-edge commercial noble-metal catalysts. The specific reaction rate increases linearly with the concentration of 1T-phase MoS2, confirming the excellent intrinsic activity of 1T-MoS2 for MAH to SA. The electron-rich Mo sites on the oxidized Mo edges of 1T-MoS2 form a pocketlike active site (HO–Mo–S–Mo–S–Mo–OH), which confines the MAH adsorption mode due to the steric effect and further promotes H2 activation due to the itinerant electrons of Mo4+ in 1T-MoS2. The strategy of constructing edge-confined active centers with specific phase composition of 2D materials opens an approach to developing highly efficient catalysts for chemical transformations.