Abstract A simple calcination method was employed to prepare a Z-scheme N-doped K4Nb6O17/g-C3N4 (KCN) heterojunction photocatalyst, in which the electronic structure of K4Nb6O17 was regulated by N-doping, and g-C3N4 was formed both on the surface and within the interlayer spaces of K4Nb6O17. The KCN composite showed profoundly improved photocatalytic activity for both H2 generation and RhB degradation compared to its counterparts. This improved performance was attributed to the synergistic effects of N-doping, which broadened its light harvesting ability, and heterojunction formation, which increased the charge separation rate. The relatively low BET specific surface area of the KCN composite had little effect on its photocatalytic activity. Based on ESR spectroscopy studies, •O2−, •OH, and h+ are the main active species in the photocatalytic degradation of RhB. Thus, it is reasonable to propose a Z-scheme photocatalytic mechanism over the KCN composite, which exhibits the dual advantages of efficient charge separation and high redox ability. Our work provides a simple approach for constructing large-scale Z-scheme heterojunction photocatalysts with high photocatalytic performance.

中文翻译：

---

Z 型 N 掺杂 K4Nb6O17/g-C3N4 异质结具有优异的可见光驱动光催化活性，用于去除有机污染物和制氢

摘要 采用简单的煅烧方法制备了 Z 型 N 掺杂 K4Nb6O17/g-C3N4 (KCN) 异质结光催化剂，其中 K4Nb6O17 的电子结构受 N 掺杂调节，g-C3N4 形成于K4Nb6O17 的表面和层间空间内。与其对应物相比，KCN 复合材料对 H2 生成和 RhB 降解的光催化活性都有显着提高。这种改进的性能归因于 N 掺杂的协同效应，这扩大了其光收集能力，以及异质结的形成，这增加了电荷分离率。KCN复合材料相对较低的BET比表面积对其光催化活性影响不大。基于 ESR 光谱研究，•O2−、•OH、h+ 是光催化降解 RhB 的主要活性物质。因此，在 KCN 复合材料上提出 Z 型光催化机制是合理的，它具有高效的电荷分离和高氧化还原能力的双重优势。我们的工作为构建具有高光催化性能的大规模 Z 型异质结光催化剂提供了一种简单的方法。