Molecular and Material Engineering of Photocathodes Derivatized with Polyoxometalate-Supported {MoS} HER Catalysts.

Molecular engineering of efficient HER catalysts is an attractive approach for controlling the spatial environment of specific building units selected for their intrinsic functionality required within the multistep HER process. As the {MoS} core derived as various coordination complexes has been identified as one as the most promising MoS-based HER electrocatalysts, we demonstrate that the covalent association between the {MoS} core and the redox-active macrocyclic {PW} polyoxometalate (POM) produces a striking synergistic effect featured by high HER performance. Various experiments carried out in homogeneous conditions showed that this synergistic effect arises from the direct connection between the {MoS} cluster and the toroidal {PW} units featured by a stoichiometry that can be tuned from two to four {MoS} cores per {PW} unit.