H₂O₂ is a green, environmentally friendly potential energy source. The photocatalytic reduction of molecular oxygen to synthesise H₂O₂ is an eco-friendly strategy compared with the anthraquinone method and H₂/O₂ direct synthesis. We proposed oxygen-enriched carbon nitride polymer (OCN) models, which were proven to more easily produce 1,4-endoperoxide species and have a high selectivity for molecular oxygen reduction to H₂O₂, rather than superoxide radicals, through theoretical calculations and experiments. The apparent quantum yield for H₂O₂ production by OCNs reached 10.2% at 420 nm under an O₂ atmosphere, which was 3.5 times higher than that of g-C₃N₄ and the activity did not decay over 20 h. OCN has a better oxygen reducibility and electron–hole separation efficiency than g-C₃N₄ and is more prone to 2-electron reduction in the ORR. This work promotes understanding of the mechanism of photocatalytic oxygen reduction and provides a new idea for the design and synthesis of new materials for the preparation of H₂O₂.

中文翻译：

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富氧的石墨氮化碳聚合物有效地将可见光驱动的选择性氧气还原为过氧化氢†

H ₂ O ₂是绿色，环保的潜在能源。与蒽醌法和H ₂ / O ₂直接合成相比，光催化还原分子氧来合成H ₂ O ₂是一种环保策略。我们提出了富氧氮化碳聚合物（OCN）模型，通过理论计算和分析，事实证明，该模型更易于产生1,4-内过氧化物，并且对分子氧还原为H ₂ O ₂而不是超氧自由基具有较高的选择性。实验。H ₂ O ₂的表观量子产率生产由OCNS的O下达到在420nm处为10.2％₂气氛中，这比GC的3.5倍₃ Ñ ₄和活性没有衰减超过20小时。与gC ₃ N ₄相比，OCN具有更好的氧还原性和电子-空穴分离效率，并且ORR中更易于2电子还原。这项工作促进了对光催化氧还原机理的理解，为设计和合成用于制备H ₂ O ₂的新材料提供了新的思路。