Efficient Photocatalytic Overall Water Splitting Induced by the Giant Internal Electric Field of a g‐C3N4/rGO/PDIP Z‐Scheme Heterojunction

Abstract A graphitic carbon nitride/rGO/perylene diimide polymer (g‐C 3 N 4 /rGO/PDIP) Z‐scheme heterojunction is successfully constructed to realize high‐flux charge transfer and efficient photocatalytic overall water splitting. A giant internal electric field in the Z‐scheme junction is built, enabling the charge separation efficiency to be enhanced dramatically by 8.5 times. Thus, g‐C 3 N 4 /rGO/PDIP presents an efficient and stable photocatalytic overall water splitting activity with H 2 and O 2 evolution rate of 15.80 and 7.80 µmol h −1 , respectively, ≈12.1 times higher than g‐C 3 N 4 nanosheets. Meanwhile, a notable quantum efficiency of 4.94% at 420 nm and solar‐to‐hydrogen energy‐conversion efficiency of 0.30% are achieved, prominently surpassing many reported g‐C 3 N 4 ‐based photocatalysts. Briefly, this work throws light on enhancing the internal electric field by interface control to dramatically improve the photocatalytic performance.