Optimizing heterojunction structure is an important way to improve photocatalytic activity. Herein, we report a novel hollow tubular CN/Nb/NbO nanoparticle Z-Scheme heterojunction, by introducing Nb ions into NbO through a reducing atmosphere during CN thermal polymerization. The optimized heterostructure showed outstanding photocatalytic hydrogen evolution activity under both UV–vis (14.93 mmol g h) and Vis (5.22 mmol g h) lights. The photocatalytic hydrogen evolution activity under UV–vis light is 26.6 and 4.75 times that of bulk CN (CN) and hollow tubular CN (HCN), respectively. The increased photocatalytic activity can be attributed to the larger specific surface area, more active sites, and enhanced light absorption capacity of the composite. Crucially, the introduction of Nb ions as the charge-carrier transport channels in the Z-scheme heterostructure improves the efficiency of photogenerated charge-carrier separation. This study provides a useful design strategy for Z-Scheme photocatalytic heterojunction structures that can utilize solar light more efficiently.

中文翻译：

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通过在空心多孔管状 C3N4 和 Nb2O5 Z 型异质结中原位构建 Nb4+ 载流子通道实现高效光催化析氢


优化异质结结构是提高光催化活性的重要途径。在此，我们报道了一种新型中空管状 CN/Nb/NbO 纳米颗粒 Z 型异质结，通过 CN 热聚合过程中的还原气氛将 Nb 离子引入到 NbO 中。优化的异质结构在紫外可见光（14.93 mmol gh）和可见光（5.22 mmol gh）光下均表现出出色的光催化析氢活性。紫外可见光下的光催化析氢活性分别是块状 CN (CN) 和空心管状 CN (HCN) 的 26.6 倍和 4.75 倍。光催化活性的增加可归因于复合材料更大的比表面积、更多的活性位点和增强的光吸收能力。至关重要的是，在 Z 型异质结构中引入 Nb 离子作为电荷载流子传输通道提高了光生电荷载流子分离的效率。这项研究为 Z 型光催化异质结结构提供了一种有用的设计策略，可以更有效地利用太阳光。