2D/2D MOF‐Based S‐Scheme Photocatalyst for Enhanced H ₂ Production and Charge Transfer

ABSTRACT Efficient charge separation remains a key challenge limiting the photocatalytic performance of metal–organic frameworks (MOFs). In a recent advance, Huang et al. developed an ultrathin 2D/2D MOF‐based S‐scheme heterojunction to overcome this limitation. By exfoliating Cu‐TCPP and Cd‐TBAPy MOFs into few‐layer nanosheets and assembling them via pH‐controlled electrostatic attraction, they formed an intimate face‐to‐face metal–organic layer (MOL) interface with a built‐in electric field. A suite of characterizations confirmed an S‐scheme band alignment that promotes directional charge transfer and maintains strong redox potentials. The optimized Cu/Cd‐MOL achieved an H 2 evolution rate of 1342 μmol h −1 g −1 , whereas a Cu/Ni‐MOL variant reached 2027 μmol h −1 g −1 with a 2.75% apparent quantum yield. This study provides a general strategy for constructing ultrathin MOF heterostructures with accelerated charge kinetics for efficient solar‐to‐hydrogen conversion.