Abstract Exploring low-cost and highly active photocatalysts is very urgent to accomplish complete removal of phenolic contaminants and overcome the limitations of the existing photocatalysts. In this study, we designed and synthesized noble metal-free TiO2 photocatalysts by introducing bismuth nanoparticles as modifiers of a TiO2 single crystal (Bi-SCTiO2). The Bi-SCTiO2 can make full use of the synergistic effect of a small band overlap and low charge carrier density (Bi) with a high conductivity (single crystal), significantly boosting the separation and migration of the photogenerated charge pairs. Therefore, the Bi-SCTiO2 photocatalyst exhibits a significantly enhanced degradation rate (12 times faster) of 4-nitrophenol than a TiO2 single crystal under simulated sunlight irradiation. Notably, the complete removal of phenolic contaminants is achieved in various water matrices, which not only successfully overcomes the incomplete degradation in many reported photocatalytic systems, but also manifests a significant practical potential for sewage disposal. Therefore, this work presents a new insight in designing and constructing noble metal-free decorated semiconductor single-crystal photocatalysts with excellent activity and cyclability.

中文翻译：

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从铋改性的 TiO2 单晶光催化剂中完全去除酚类污染物

摘要 探索低成本、高活性的光催化剂对于实现酚类污染物的完全去除和克服现有光催化剂的局限性非常紧迫。在这项研究中，我们通过引入铋纳米颗粒作为 TiO2 单晶 (Bi-SCTiO2) 的改性剂，设计并合成了不含贵金属的 TiO2 光催化剂。Bi-SCTiO2可以充分利用小带重叠和低电荷载流子密度（Bi）的协同效应，具有高电导率（单晶），显着促进光生电荷对的分离和迁移。因此，在模拟阳光照射下，Bi-SCTiO2 光催化剂对 4-硝基苯酚的降解速度比 TiO2 单晶显着提高（快 12 倍）。尤其，在各种水基质中实现了酚类污染物的完全去除，这不仅成功地克服了许多报道的光催化系统中不完全降解的问题，而且在污水处理方面显示出巨大的实际潜力。因此，这项工作为设计和构建具有优异活性和循环性的无贵金属装饰的半导体单晶光催化剂提供了新的见解。