Boosting Photocatalytic Hydrogen Production from Water in Poly(heptazine imides): The Role of the Mg2+-OH2-Pt Interface
Palavras-chave:
Hydrogen Evolution Reaction (HER), Crystalline Carbon Nitrides, Poly(Heptazine imides), in situ XANESResumo
In response to the climate crisis and growing demand for sustainable energy, molecular hydrogen has emerged as a key pillar in the transition toward carbon neutrality. Among green production routes, photocatalytic H2 evolution stands out as a promising method for storing solar energy as chemical energy. Here, we report enhanced H2 evolution via magnesium incorporation into semi-crystalline carbon nitride. Mg-doped poly(heptazine imide) (Mg-PHI) frameworks exhibited outstanding photoactivity, achieving H2 evolution rates up to 6452 μmol g-1 h-1 and an AQY near 6% under visible light. A comprehensive analysis combining photocatalytic performance and in situ XANES revealed a cooperative synergy between Mg2+ ions embedded in PHI and photodeposited Pt cocatalysts. We identified a Mg2+–OH2–Pt interfacial domain near active sites, which facilitates charge transfer and boosts H2 evolution. These results highlight Mg2+ doping as a promising strategy for broader application across photocatalytic systems, with strong potential to impact sustainable H2 production.
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