Fe-MIL tuned and bound with Bi4O5Br2 for boosting photocatalytic reduction of CO2 to CH4 under simulated sunlight

Abstract

A series of composites composed of Bi₄O₅Br₂ and Fe-MIL were successfully fabricated for mimicking sunlight-driven photocatalytic reduction of CO₂. Herein, Bi₄O₅Br₂, as a modulator of solid acids, could turn NH₂-MIL-101(Fe) into NH₂-MIL-88B(Fe) completely at 0.07 wt% catalytic loading, where further addition could construct the corresponding composites of Bi₄O₅Br₂ and NH₂-MIL-88B(Fe). The highest activity in the photocatalytic reduction of CO₂ was achieved at 7.96 μmol g⁻¹ h⁻¹ of CH₄ at 3.28 wt% of Bi₄O₅Br₂. Besides, this catalyst possessed high photostability during the recycling experiments and the mechanism of this process was thoroughly explored. This study provides a novel strategy employing solid acid modulators for regulating the structure and morphology of MOFs showing high activity and stability in the photocatalytic reduction of CO₂ to CH₄.