Spontaneous generation of an atomically dispersed Mo and MoS2 coupling catalyst via reaction induction transformation for enhancing local hydrogen concentration in hydrogenation

The development of a synergistic coupling catalyst at the atomic scale for slurry-phase hydrogenation of vacuum residue (VR) is extremely challenging. Herein, we designed and constructed a robust coupling catalyst comprising Mo single atoms and MoS2 (Mo SAs–MoS2) using a reaction induction transformation strategy. The spontaneous generation of Mo SAs–MoS2 synergistically promoted H2 activation and enhanced local active hydrogen concentration in the hydrogenation of VR. Benefiting from the strong hydrogen concentration distribution in MoS2 and Mo SAs, the catalyst revealed remarkable hydrogenation performance toward VR with a TOFT of up to 0.39 s−1, liquid product yield of 92 wt%, and coke content of 0.6 wt%. Theoretical calculations revealed that the synergistic action of Mo SAs–MoS2 facilitated electron transfer between Mo species and reactants, reducing the desorption energy barriers for H2 and anthracene and thereby promoting the hydrogenation of VR. This work provides a novel idea for the design of efficient coupling catalysts for strengthening local active hydrogen concentration in the hydrogenation of VR, and this concept can be applied to other hydrogenation systems.