Mesoporous black N-TiO_2−x hollow spheres are successfully fabricated through a facile evaporation-induced self-assembly (EISA) process, coupled with an etching procedure and an in-situ solid-state chemical reduction strategy. The resultant black N-TiO_2−x hollow spheres with high crystallinity possess a narrow band gap of ∼2.37 eV, a large specific surface area of ∼128 m² g⁻¹, and a well defined hollow sphere structure, which exhibit excellent visible-light-driven photocatalytic performance for degradation of phenol, reduction of Cr(IV), and hydrogen production. The photocatalytic reaction apparent rate constants (k) of the black N-TiO_2−x for phenol degradation and Cr(IV) reduction are ∼5 and 6 times higher than that of pristine TiO₂, and hydrogen production rate for N-TiO_2−x is ∼160 μmol h⁻¹, which is ∼7 folds higher than that of pristine one. The excellent photocatalytic and photoreduction property can be attributed to the synergy effect of N and Ti³⁺ codoping narrowing the band gap, the high specific surface area offering more surface active sites, and the mesoporous hollow structure favoring light harvesting and refraction.

介孔黑色N-TiO _2-x空心球是通过简便的蒸发诱导自组装（EISA）工艺，蚀刻工艺和原位固态化学还原策略成功制造的。所得的具有高结晶度的黑色N-TiO _2-x中空球具有约2.37 eV的窄带隙，约128 m ² g ^-1的大比表面积和良好定义的中空球结构，显示出优异的可见光-光驱动的光催化性能，可降解苯酚，还原Cr（IV）和制氢。黑色N-TiO _2-x的光催化反应表观速率常数（k）苯酚降解和Cr（IV）还原的速率分别是原始TiO _2的5倍和6倍，N-TiO _2-x的产氢速率为160μmolh ^-1，是原始TiO _2的7倍。原始的。优异的光催化和光还原性能可归因于N和Ti ³⁺共掺杂使带隙变窄，高比表面积提供更多表面活性位点以及有利于光收集和折射的中孔空心结构的协同效应。