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

A graphitic carbon nitride/rGO/perylene diimide polymer (g-C3N4/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-C3N4/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 mu mol h(-1), respectively, approximate to 12.1 times higher than g-C3N4 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-C3N4-based photocatalysts. Briefly, this work throws light on enhancing the internal electric field by interface control to dramatically improve the photocatalytic performance.

Automated summary

The research successfully constructed a graphitic carbon nitride/rGO/perylene diimide polymer (g-C3N4/rGO/PDIP) Z-scheme heterojunction, achieving high-efficiency and stable photocatalytic overall water splitting activity. By building a giant internal electric field in the Z-scheme junction, the charge separation efficiency was significantly improved, leading to higher hydrogen and oxygen evolution rates, quantum efficiency, and solar-to-hydrogen energy conversion efficiency.