Photocatalytic Hydrogen Generation from a Visible-Light-Responsive Metal–Organic Framework System: Stability versus Activity of Molybdenum Sulfide Cocatalysts

[Image: see text] We report the use of two earth abundant molybdenum sulfide-based cocatalysts, Mo(3)S(13)(2–) clusters and 1T-MoS(2) nanoparticles (NPs), in combination with the visible-light active metal–organic framework (MOF) MIL-125-NH(2) for the photocatalytic generation of hydrogen (H(2)) from water splitting. Upon irradiation (λ ≥ 420 nm), the best-performing mixtures of Mo(3)S(13)(2–)/MIL-125-NH(2) and 1T-MoS(2)/MIL-125-NH(2) exhibit high catalytic activity, producing H(2) with evolution rates of 2094 and 1454 μmol h(–1) g(MOF)(–1) and apparent quantum yields of 11.0 and 5.8% at 450 nm, respectively, which are among the highest values reported to date for visible-light-driven photocatalysis with MOFs. The high performance of Mo(3)S(13)(2–) can be attributed to the good contact between these clusters and the MOF and the large number of catalytically active sites, while the high activity of 1T-MoS(2) NPs is due to their high electrical conductivity leading to fast electron transfer processes. Recycling experiments revealed that although the Mo(3)S(13)(2–)/MIL-125-NH(2) slowly loses its activity, the 1T-MoS(2)/MIL-125-NH(2) retains its activity for at least 72 h. This work indicates that earth-abundant compounds can be stable and highly catalytically active for photocatalytic water splitting, and should be considered as promising cocatalysts with new MOFs besides the traditional noble metal NPs.