Amorphous solid

Catalysis

Engineering

Materials science

Water splitting

Telecommunications

Computer science

Chemical engineering

Homojunction

Geology

Oceanography

Nanotechnology

Organic chemistry

Degradation (telecommunications)

Heterojunction

Crystallography

Chemistry

Seawater

Photocatalysis

Optoelectronics

Applied Surface Science

Photocatalytic water and seawater splitting into H2 is a promising strategy to attract the attention of researchers due to unique advantages including environment-friendly, cost-effectiveness and strong applicability. In this work, the high-crystalline/amorphous g-C3N4 (HCCN/ACN) S-scheme homojunctions are fabricated by solvothermal method and applied in photocatalytic H2 production no matter in water or seawater environments. The results of characterizations and experiments confirm that HCCN/ACN-6:4 S-scheme homojunction possesses optimal photocatalytic H2 evolution rate in water (5.534 mmol h−1 g−1) and seawater (3.147 mmol h−1 g−1) respectively, which is ascribed to the following reasons: (i) the accelerated interface charge transfer in distinctive S-scheme homojunction could produce more active groups to participate in photocatalytic reaction; (ii) the improved specific surface area in HCCN/ACN-6:4 can provide more active sites on the surface to promote photocatalytic H2 production; (iii) enhanced hydrophilic in HCCN with abundant photo-reaction reduced sites is beneficial to photocatalytic H2 evolution reaction between electrons and water molecules. This work provides a novel prospect for designing S-scheme homojunction photocatalyst with outstanding photocatalytic performance.

High-crystalline/amorphous g-C3N4 S-scheme homojunction for boosted photocatalytic H2 production in water/simulated seawater: Interfacial charge transfer and mechanism insight