Photocatalysis is a promising technology for energy and environment applications. Herein, a dual-defect heterojunction system of TiO₂ hierarchical microspheres with oxygen vacancies modified with ultrathin MoS_2−x nanosheets (MoS_2−x @TiO₂-OV) is designed for simultaneously degrading pollutants and evolving hydrogen. MoS_2−x @TiO₂-OV exhibits a dramatically enhanced photocatalytic activity with a H₂ evolution rate of 2985.16 μmol g⁻¹h⁻¹. In treating the simulated pharmaceutical wastewater, MoS_2−x @TiO₂-OV is capable of purifying various refractory contaminants, with the highest H₂ evolution rate of 41.59 μmol g⁻¹h⁻¹ during enrofloxacin degradation. While treating the simulated coking wastewater, the catalyst achieves a H₂ evolution rate of 102.72 μmol g⁻¹h⁻¹ and a mineralization rate of 50%. Computational studies suggest that the dual-defect is superior for the adsorption of H* and producing·OH (‘dual-defect boosted dual-function’). Also, the dual-defect sites significantly boosted the charge-carrier separation and transfer efficiencies. This work highlights the crucial role of defect engineering to develop the energy-recovering wastewater treatment approaches.

光催化是一种有前景的能源和环境应用技术。在此，设计了一种由超薄 MoS _2-x纳米片（MoS _2-x @TiO ₂ -OV）修饰的具有氧空位的 TiO ₂分级微球的双缺陷异质结系统，用于同时降解污染物和释放氢气。MoS _2-x @TiO ₂ -OV 表现出显着增强的光催化活性，H ₂析出率为2985.16 μmol g ^-1 h ^-1。在处理模拟制药废水时，MoS _2−x @TiO ₂-OV 能够净化各种难处理的污染物，在恩诺沙星降解过程中，H ₂析出率最高，为 41.59 μmol g ^-1 h ^-1。在处理模拟焦化废水时，催化剂的H ₂析出率为102.72 μmol g ^-1 h ^-1，矿化率为50%。计算研究表明，双缺陷在吸附 H* 和产生·OH（“双缺陷增强双功能”）方面更胜一筹。此外，双缺陷位点显着提高了电荷载流子分离和转移效率。这项工作突出了缺陷工程在开发能量回收废水处理方法中的关键作用。