Rational design of a Z-scheme ZIF-67/In2O3 heterojunction with a built-in electric field and defects for photocatalytic CO2 conversion

Abstract

The escalating global warming crisis, driven by excessive CO₂ emissions, necessitates the development of innovative strategies for carbon neutrality. The photocatalytic CO₂ reduction reaction (CO₂RR) offers a promising pathway for converting CO₂ into sustainable hydrocarbon fuels using solar energy. However, achieving high efficiency and selectivity in the photocatalytic CO₂RR remains a significant challenge. In this study, we rationally designed a Z-scheme ZIF-67/In₂O₃ heterojunction with a built-in electric field and defects to enhance the selective photocatalytic conversion of CO₂ to CO. The ZIF-67/In₂O₃ heterojunction exhibited a remarkable CO yield of 6805.23 μmol h⁻¹ g⁻¹ with a high selectivity of 97.31%. This enhancement originated from the synergistic effect of the Z-scheme heterojunction and oxygen vacancies, which significantly improved charge separation efficiency and CO₂ activation. Density functional theory (DFT) calculations further elucidated the charge transfer mechanism and CO₂ adsorption behavior at the heterojunction interface. This study provides a novel strategy for designing highly efficient photocatalysts for selective CO₂ reduction, contributing to the development of sustainable energy solutions.