Thiomolybdate clusters: from homogeneous catalysis to heterogenization and active sites

Abstract

Thiomolybdates are molecular molybdenum-sulfide clusters formed from Mocenters and sulfur-based ligands. For decades, they have attracted the interestof synthetic chemists due to their unique structures and their relevance inbiological systems, e.g., as reactive sites in enzymes. More recently,thiomolybdates are explored from the catalytic point of view and applied ashomogeneous and molecular mimics of heterogeneous molybdenum sulfidecatalysts. This review summarizes prominent examples ofthiomolybdate-based electro- and photocatalysis and provides acomprehensive analysis of their reactivities under homogeneous andheterogenized conditions. Active sites of thiomolybdates relevant for thehydrogen evolution reaction are examined, aiming to shed light on the linkbetween cluster structure and performance. The shift from solution-phase tosurface-supported thiomolybdates is discussed with a focus on applicationsin electrocatalysis and photocatalysis. The outlook highlights current trendsand emerging areas of thiomolybdate research, ending with a summary ofchallenges and key takeaway messages based on the state-of-the-art research.