A sol–gel method was used to synthesize TiO₂ nanoparticles doped with varying amounts of Mn. The physico-chemical properties of the synthesized nanoparticles were characterized using X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM) and diffuse reflection spectroscopy (DRS). The XRD results indicated that the anatase phase was the major phase of TiO₂, while a minor rutile phase was observed in the Mn-doped TiO₂ 0.2 wt.% and 0.3 wt.% samples. The TEM analysis showed that the Mn atoms existed in different oxidation states, including Mn${}^{2+}$, Mn${}^{3+}$, Mn${}^{4+}$ and Mn${}^{7+}$, and that the nanoparticles had a spherical-like morphology with a size ranging from 10$$nm. The narrowest band gap of 2.80$$eV was observed in the Mn-doped TiO₂ 0.2 wt.% sample. The photocatalytic activity of the synthesized nanoparticles was evaluated for methylene blue (MB) photodegradation and Escherichia coli (E. coli) photokilling under visible light irradiation. The MB degradation efficiency was found to be the highest in the Mn-doped TiO₂ 0.2 wt.% sample, with a removal efficiency of 96% and a degradation rate constant of 0.08 1/min. The degradation efficiency decreased in the following order: Mn-doped TiO₂ 0.1 wt.%, 0.3 wt.% and undoped TiO₂. Similarly, complete E. coli photokilling was achieved only in the Mn-doped TiO₂ 0.2 wt.% sample, while some residual E. coli was observed in the other doping nanoparticles and undoped TiO₂. In summary, the results suggest that Mn doping significantly improved the photocatalytic activity of TiO₂ nanoparticles, and the Mn-doped TiO₂ 0.2 wt.% sample exhibited the highest efficiency in both MB photodegradation and E. coli photokilling under visible light irradiation.

采用溶胶-凝胶法合成了掺杂不同量Mn的TiO _{2纳米颗粒。}使用X射线衍射（XRD）、X射线光电子能谱（XPS）、透射电子显微镜（TEM）和漫反射光谱（DRS）对合成纳米粒子的物理化学性质进行了表征。XRD结果表明，锐钛矿相是TiO ₂的主要相，而在Mn掺杂的TiO ₂ 0.2 wt.%和0.3 wt.%样品中观察到少量金红石相。TEM分析表明Mn原子以不同的氧化态存在，其中Mn${}^{2+}$, 锰${}^{3+}$, 锰${}^{4+}$和锰${}^{7+}$，并且纳米颗粒具有球形形态，尺寸范围为 10$$纳米。最窄带隙为2.80$$在 Mn 掺杂 TiO ₂ 0.2 wt.% 样品中观察到 eV。评估了合成纳米粒子在可见光照射下的亚甲蓝（MB）光降解和大肠杆菌（E.coli）光杀伤活性。_{发现Mn掺杂TiO 2} 0.2 wt.%样品中MB降解效率最高，去除效率为96%，降解速率常数为0.08 1/min。降解效率按以下顺序降低：Mn掺杂的TiO ₂ 0.1wt.%、0.3wt.%和未掺杂的TiO ₂。类似地，仅在 Mn 掺杂 TiO _{2中实现了完全的}大肠杆菌光杀灭0.2 wt.%的样品，而在其他掺杂纳米粒子和未掺杂的TiO _{2中观察到一些残留的}大肠杆菌。综上所述，结果表明，Mn掺杂显着提高了TiO ₂纳米颗粒的光催化活性，并且Mn掺杂的TiO ₂ 0.2 wt.%样品在可见光照射下的MB光降解和大肠杆菌光杀伤效率均最高。