Defective TiO₂ nanocrystals (D-TiO₂) were synthesized by a simple, mild and green sol–gel hydrothermal method. The as-prepared sample possesses a high specific surface area of 173.6 m²/g and high crystallinity of anatase phase without any calcination. Raman, EPR and XPS spectrum confirmed the existence of oxygen vacancies in D-TiO₂. These oxygen vacancies provide D-TiO₂ with visible-light photocatalytic activity, as demonstrated by the degradation of Rhodamine B (RhB). The degradation pathway of RhB over D-TiO₂ was investigated, and the possible photocatalytic mechanism was also proposed. The excellent photocatalytic property of D-TiO₂ was mainly attributed to the synergistic effect between the high surface area and abundant oxygen vacancies. This work presents a new route to synthesize high-performance visible-light-responsive TiO₂ photocatalyst.

通过简单，温和且绿色的溶胶-凝胶水热法合成了有缺陷的TiO ₂纳米晶体（D-TiO ₂）。所制备的样品具有173.6m ² / g的高比表面积和无任何煅烧的高锐钛矿相结晶度。拉曼光谱，EPR和XPS光谱证实D-TiO _2中存在氧空位。如罗丹明B（RhB）的降解所证明，这些氧空位为D-TiO ₂提供了可见光光催化活性。研究了RhB在D-TiO _2上的降解途径，并提出了可能的光催化机理。D-TiO ₂的优异光催化性能主要归因于高表面积和丰富的氧空位之间的协同效应。这项工作为合成高性能可见光响应的TiO ₂光催化剂提供了一条新途径。