Development of a bismuth-based metal-organic framework for photocatalytic hydrogen production

Abstract

A novel 3D bismuth-organic framework (called Bi-TBAPy) single crystal was synthesized by employing 1,3,6,8-tetrakis(p-benzoic acid)pyrene (H 4 TBAPy) as an organic linker. The study demonstrates that the Bi-TBAPy not only possesses good chemical stability and suitable band edge positions for promising photocatalytic H 2 evolution, but it also exhibits a typical ligand-to-metal charge transfer for favorable charge separation. The photocatalytic H 2 evolution rates on the as-obtained Bi-TBAPy with different cocatalysts modified were examined with triethanolamine as the sacrificial reagent. Based on this, the hydrogen evolution rate of 140 μmol h −1 g −1 was obtained on the optimized sample with a loading of 2 wt % Pt as a cocatalyst. To the best of our knowledge, this is the first bismuth-based metal-organic framework (MOF) that functions as an effective photocatalyst for photocatalytic water reduction. Our study not only adds a new member to the family of photocatalyst materials, but also reveals the importance of cocatalyst modification in improving photocatalytic activity of MOFs. A new 3D bismuth-organic framework (Bi-TBAPy) with ligand-to-metal charge transfer (LMCT) process was synthesized to exhibit for the first time robust photocatalytic water reduction, demonstrating its promising future in solar energy conversion.