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

• DOI: 10.1021/acsami.8b10010
• Publication Date: 2018-08-20T15:19:59Z
• Authors: Tu N. Nguyen; Stavroula Kampouri; Bardiya Valizadeh; Wen Luo; Daniele Ongari; Ophélie Marie Planes; Andreas Züttel; Berend Smit; Kyriakos C. Styli...
• Keywords: Engineering; Affordable and Clean Energy; metal−organic framework; hydrogen; Chemical Sciences; molybdenum sulfide; 02 engineering and technology; metal-organic framework; Nanoscience & Nanotechnology; 0210 nano-technology; photocatalysis; 7. Clean energy; visible light

We report the use of two earth abundant molybdenum sulfide-based cocatalysts, Mo3S132- clusters and 1T-MoS2 nanoparticles (NPs), in combination with the visible-light active metal-organic framework (MOF) MIL-125-NH2 for the photocatalytic generation of hydrogen (H2) from water splitting. Upon irradiation (λ ≥ 420 nm), the best-performing mixtures of Mo3S132-/MIL-125-NH2 and 1T-MoS2/MIL-125-NH2 exhibit high catalytic activity, producing H2 with evolution rates of 2094 and 1454 μmol h-1 gMOF-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 Mo3S132- 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-MoS2 NPs is due to their high electrical conductivity leading to fast electron transfer processes. Recycling experiments revealed that although the Mo3S132-/MIL-125-NH2 slowly loses its activity, the 1T-MoS2/MIL-125-NH2 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.