An in situ derived MOF@In2S3 heterojunction stabilizes Co(ii)-salicylaldimine for efficient photocatalytic formic acid dehydrogenation

Abstract

We report here the hierarchical construction of a molecular Co(II)-salicylaldimine catalyst and an in situ derived In₂S₃ semiconductor in a MOF@In₂S₃ heterojunction through sequentially controllable in situ etching and post-synthetic modification for photocatalytic hydrogen production from formic acid. The enhanced catalyst stability and facilitated charge carrier mobility between the In₂S₃ photosensitizers and Co catalyst realize a superior H₂ production rate of 18 746 μmol g⁻¹ h⁻¹ (selectivity > 99.9%) with a turnover number (TON) of up to 6146 in 24 h (apparent quantum efficiency of 3.8% at 420 nm), indicating a 165-fold enhancement over that of the pristine MOF. This work highlights a powerful strategy for synergistic Earth-abundant metal-based MOF photocatalysis in promoting H₂ production from FA.