Substituent Effect to Fine-Tune Energy Levels of Atom-Precise [MoOS ] Modified Copper(I) Thiolate Clusters Boosting Recyclable Photocatalysis.

The propulsion of photocatalytic hydrogen (H ) production is limited by the rational design and regulation of catalysts with precise structures and excellent activities. In this work, the [MoOS ] unit is introduced into the Cu clusters to form a series of atomically-precise Mo -Cu bimetallic clusters of [Cu (MoOS ) (C H (CH )S) (P(C H -R) ) ] ⋅ xCH CN (R=H, CH , or F), which show high photocatalytic H evolution activities and excellent stability. By electron push-pull effects of the surface ligand, highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) levels of these Mo -Cu clusters can be finely tuned, promoting the resultant visible-light-driven H evolution performance. Furthermore, Mo -Cu clusters loaded onto the surface of magnetic Fe O carriers significantly reduced the loss of catalysts in the collection process, efficiently addressing the recycling issues of such small cluster-based catalyst. This work not only highlights a competitively universal approach on the design of high-efficiency cluster photocatalysts for energy conversion, but also makes it feasible to manipulate the catalytic performance of clusters through a rational substituent strategy.