Defect-enriched BiOIO 3 /Ti3C2 MXene 2D/2D Schottky-type heterostructure for efficient and selective CH 4 production via CO 2 photoreduction: Unveiling the roles of defect inclusion and Ti3 C2 MXene co-catalyst

The photoreduction of CO 2 using solar energy to produce energy-efficient fuels is a sustainable technology that addresses energy needs while reducing carbon emissions. However, synthesizing efficient and robust photocatalysts for this process is challenging. This study introduces a viable approach for highly selective CO 2 photoreduction to CH 4 production by integrating defect-enriched BiOIO 3 (DEBI) with a Ti 3 C 2 (TC) MXene co-catalyst, forming an efficient 2D/2D Schottky-type heterostructure. The DEBI, enhanced with precise defect engineering, showed improved light absorption and charge separation efficiency. In tandem, the TC MXene co-catalyst facilitated rapid electron transfer and significantly minimized charge recombination. Consequently, the DEBI/TC-2 heterostructure, with an optimal 2 wt% TC MXene loading, achieved a CH 4 yield of 52.8 mu mol h -1 g -1 , representing a remarkable 20.5- and 6.3-fold increase over pristine BiOIO 3 and DEBI, respectively. The Schottky-type 2D/2D heterostructure also demonstrated an impressive apparent quantum yield of 0.72%, 99% CH 4 selectivity over H 2 generation, and remarkable stability across multiple cycles. This study underscores the synergistic advantages of defect engineering and MXene co-catalyst integration in a single system, proposing a novel direction for designing highly efficient photocatalysts for solar-driven CO 2 reduction in energy-efficient fuel production. (c) 2024 Published by Elsevier Ltd on behalf of The editorial office of Journal of Materials Science & Technology.