Boosting selective hydrogenation through hydrogen spillover on supported-metal catalysts at room temperature

Highly efficient hydrogenation of substrates with strong absorption on metals at low temperatures is a long-term pursuit. However, due to the scaling relationship of high binding energies on metals, the poor activity and/or selectivity are frequently observed. Herein, we described a strategy of hydrogen spillover to enable highly selective hydrogenation at low temperatures by constructing the dual-active site in PtCo alloys supported on hydroxyl-abundant cobalt borate (CoBOx), delivering a high TOF of 2479 h−1 (two orders of magnitude over PtCo/C) and 94.5 % selectivity of cinnamyl alcohol at room temperature. Experimental and theoretical investigations suggest that hydrogen and reactants are activated on PtCo alloys and second active sites on CoBOx support, respectively. Hydrogenation sequentially occurs on CoBOx via hydrogen spillover from metal to support. Easy desorption of surface-bounded products substantially re-generates the active sites. Spillover hydrogenation on dual-active site provides a novel strategy for energy-efficiently selective hydrogenation.