Efficient generation of reactive oxygen radicals is key to improving the activity of photocatalytic degradation for indoor volatile organic compounds (VOCs). In this study, BaTiO₃ (BTO) nanoparticles co-modified by Cu(II) and periodic acid (PA) were synthesized by a simple impregnation method to construct a visible-light-driven multiple-radicals photocatalytic system for indoor VOC elimination. The results show that PA interacts with BTO as well as the surface-grafted Cu(II) clusters to produce the BTO–Cu–O–I–(OH)_n complex, improving visible light absorption efficiency and photogenerated charge lifetime. Furthermore, PA, with its hygroscopic properties, facilitates the formation of a water film on the surface, which contributes to the dissolution and accumulation of gaseous pollutants. Remarkably, hydroxyl radicals (•OH) and superoxide anion radicals (•O₂^–) are rapidly generated via Cu(II)/Cu(I) redox reactions with the help of hydrophilic PA. As expected, our optimized samples exhibit 26.3 times higher photocatalytic decomposition activity of gaseous isopropyl alcohol into CO₂ compared to pristine barium titanate.

中文翻译：

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自由基介导的光催化高效室内空气净化：自 润湿 BaTiO3 与 Cu（II） 簇和高碘酸盐共改性的案例研究


有效生成活性氧自由基是提高室内挥发性有机化合物 （VOC） 光催化降解活性的关键。本研究通过简单的浸渍方法合成了由 Cu（II） 和高碘酸 （PA） 共改性的 BaTiO₃ （BTO） 纳米颗粒，构建了用于室内 VOC 消除的可见光驱动的多自由基光催化体系。结果表明，PA 与 BTO 以及表面接枝的 Cu（II） 团簇相互作用，产生 BTO-Cu-O-I-（_OH）n络合物，提高了可见光吸收效率和光生电荷寿命。此外，PA 具有吸湿性，有助于在表面形成水膜，这有助于气态污染物的溶解和积累。值得注意的是，羟基自由基 （•OH） 和超氧阴离子自由基 （•O₂^–） 是在亲水性 PA 的帮助下通过 Cu（II）/Cu（I） 氧化还原反应迅速生成的。正如预期的那样，与原始钛酸钡相比，我们优化的样品表现出气态异丙醇转化为 CO₂ 的光催化分解活性高 26.3 倍。