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The interaction of water molecule with catalysts is crucial to photocatalysis, but the surface property manipulation still remains a great challenge. In this study, we report an in situ multiple heteroelement (sodium, oxygen, and iodide) doping strategy based on a molten salt-assisted route to prepare a green-colored carbon nitride (GCN). The as-prepared GCN yields 25.5 times higher H 2 evolution rate than that of bulk polymeric carbon nitride under visible light. Experimental characterization data demonstrate that the GCN delivers upshift of the conduction band and increased specific surface area and hydrophilicity. As confirmed by time-resolved PL spectra, DMPO spin-trapping EPR analysis, and so on, the excellent activity is dominantly ascribed to the greatly enhanced hydrophilicity and, subsequently, efficient interfacial charge transfer and hydrogen liberation. Moreover, through surface charge modification, the GCN also shows an increased degradation activity of rhodamine B. This work highlights the importance of surface modulation through multiple earthabundant element incorporation for designing of advanced and practical photocatalysts.

Covalent organic frameworks (COFs) are a category of promising materials in the field of solar-driven hydrogen (H2) evolution, but their applications are limited by the speedy recombination of photoinduced charge carriers and the absorption of marginal visible light. Herein, a 2D–2D SnS2/TpPa-1-COF heterojunction photocatalyst was prepared via a one-step hydrothermal route to relieve the abovementioned shortcomings. The results show that the obtained 2D–2D SnS2/TpPa-1-COF heterojunctions not only speed up the separation of photogenerated charge carriers but also facilitate the H2 production kinetics and expand the range of visible light response to orange light (600 nm). Especially, the maximum photocatalytic H2 production rate of the 2D–2D SnS2/TpPa-1-COF heterojunction without the addition of cocatalyst Pt reaches 37.11 μmol h–1, which is 21.7-fold and 2-fold higher than those of individual TpPa-1-COF and 3 wt % Pt/TpPa-1-COF, respectively. This work indicates that the synthesis of cheap COF-based photocatalysts for high-efficiency solar energy utilization is a feasible approach to boost the photocatalytic H2 performance.

A challenge in photocatalysis consists in improving the efficiency by harnessing a large portion of the solar spectrum. We report the design and realization of a robust molecular-semiconductor photocatalytic system (MSPS) consisting of an earth-abundant phytic acid nickel (PA-Ni) biomimetic complex and polymeric carbon nitride (PCN). The MSPS exhibits an outstanding activity at l = 940 nm with high apparent quantum efficiency (AQE) of 2.8 %, particularly l > 900 nm, as it outperforms all reported state-of-the-art nearinfrared (NIR) hybrid photocatalysts without adding any noble metals. The optimum hydrogen (H 2) production activity was about 52 and 64 times higher with respect to its pristine counterpart under the AM 1.5 G and visible irradiation, respectively, being equivalent to the platinum-assisted PCN. This work sheds light on feasible avenues to prepare highly active, stable, cheap NIR-harvesting photosystems toward sustainable and scalable solar-to-H 2 production.

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