Dual Z-Scheme BiOCl/g-C₃N₄/Ag₂CrO₄ Heterojunction for Boosting Photocatalytic CO₂ Reduction

In this work, a ternary BiOCl/g-C3N4/Ag2CrO4 composite with a dual Z-scheme heterojunction was prepared based on a g-C3N4 photocatalyst and applied in the photocatalytic reduction of CO2. The optimal CH4 and CO yields of the ternary composite catalyst could be achieved on BOC/CN/ACO-1% with 81.21 and 30.20 μmol g–1 for 6 h, respectively, which was considerably enhanced compared to that for pure g-C3N4. The apparent quantum efficiency was achieved to be 2.68% for the BOC/CN/ACO-1% catalyst in the photoreduction of CO2 at 420 nm. This performance enhancement resulted from constructing the dual Z-scheme and the improved light response, which had efficient charge migration and an excellent response to sunlight. This study provides a vital reference for developing dual Z-scheme heterojunction catalysts for the photocatalytic reduction of CO2.