Abstract Normal photocatalysts cannot effectively remove low-concentration NO because of the high recombination rate of the photogenerated carriers. To overcome this problem, S-scheme composites have been developed to fabricate photocatalysts. Herein, a novel S-scheme Sb2WO6/g-C3N4 nanocomposite was fabricated by an ultrasound-assisted method, which exhibited excellent performance for photocatalytic ppb-level NO removal. Compared with the pure constituents of the nanocomposite, the as-prepared 15%-Sb2WO6/g-C3N4 photocatalyst could remove more than 68% continuous-flowing NO (initial concentration: 400 ppb) under visible-light irradiation in 30 min. The findings of the trapping experiments confirmed that •O2− and h+ were the important active species in the NO oxidation reaction. Meanwhile, the transient photocurrent response and PL spectroscopy analyses proved that the unique S-scheme structure of the samples could enhance the charge separation efficiency. In situ DRIFTS revealed that the photocatalytic reaction pathway of NO removal over the Sb2WO6/g-C3N4 nanocomposite occurred via an oxygen-induced route. The present work proposes a new concept for fabricating efficient photocatalysts for photocatalytic ppb-level NO oxidation and provides deeper insights into the mechanism of photocatalytic NO oxidation.

中文翻译：

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S-scheme Sb2WO6/g-C3N4 光催化剂具有增强的可见光诱导光催化 NO 氧化性能

摘要 由于光生载流子的高复合率，普通光催化剂不能有效去除低浓度NO。为了克服这个问题，人们开发了 S 型复合材料来制造光催化剂。在此，通过超声辅助方法制备了一种新型 S 型 Sb2WO6/g-C3N4 纳米复合材料，该复合材料在光催化 ppb 级 NO 去除方面表现出优异的性能。与纳米复合材料的纯成分相比，所制备的 15%-Sb2WO6/g-C3N4 光催化剂在可见光照射下可在 30 分钟内去除超过 68% 的连续流动 NO（初始浓度：400 ppb）。捕集实验的结果证实•O2-和h+是NO氧化反应中的重要活性物质。同时，瞬态光电流响应和PL光谱分析证明样品独特的S型结构可以提高电荷分离效率。原位 DRIFTS 揭示了 Sb2WO6/g-C3N4 纳米复合材料上 NO 去除的光催化反应途径是通过氧诱导途径发生的。目前的工作提出了一种制备用于光催化 ppb 级 NO 氧化的高效光催化剂的新概念，并为光催化 NO 氧化的机理提供了更深入的见解。