ZIF-8/g-C3N4 photocatalysts: enhancing CO2 reduction through improved adsorption and photocatalytic performance

Abstract

Nowadays, the widespread concern over controlling CO₂ emissions and mitigating the adverse effects of greenhouse gases on global climate has attracted significant attention. In this study, g-C₃N₄ was synthesized by thermopolymerizing urea. Subsequently, ZIF-8 was combined with g-C₃N₄ using an in situ deposition method, resulting in the fabrication of ZIF-8/g-C₃N₄ composite photocatalysts at various molar ratios. Effective incorporation of ZIF-8 into g-C₃N₄ suppressed the recombination of photogenerated electrons and holes, thereby enhancing CO₂ capture capacity and preserving light absorption capabilities. The ZIF-8/g-C₃N₄ composite demonstrates excellent photocatalytic performance for CO₂ reduction, where the optimized material exhibited a CO₂ adsorption capacity 1.52 times that of pure g-C₃N₄ and increased the conversion of CO₂ to CH₄ by more than sevenfold. This study harnesses the superior CO₂ adsorption properties of metal–organic frameworks to develop more efficient photocatalysts, enhancing CO₂ conversion efficacy and offering insights for developing efficient photocatalysts that utilize CO₂.