Dual-Atomic-Site-Integrated photocatalysts for green energy synthesis

Dispersing active metals into theoretical atomic level has emerged as a cost-effective means for constructing catalysts, which are considered single-atom catalysts (SACs). SACs are integrated with various photocatalysts to serve as efficient platforms for solar energy conversion. Though SACs exhibit superior catalytic activity and selectivity owing to their maximum atomic utilization and high versatility of surrounding atomic configurations, the nature of SACs containing only one type of active site limits various chain reactions, inhibiting catalytic performance. To overcome these limitations, dual atom catalysts (DACs) have emerged as a new inventive material for boosting photocatalytic reactions. Thus, this review discusses the limitations of SACs and relative advantages of DACs, synthesis of dual atom sites on various substrates, identification of dual atomic sites through characterizations, and applications of DACs in various photocatalytic energy harvesting such as H2 production, CO2 reduction, and N2 reduction. Finally, perspectives and future directions for increasing the photocatalytic performance of DACs-integrated photocatalysts are proposed.