Chitosan microbeads with C-doped TiO₂, N-doped TiO₂ and C,N-codoped TiO₂ were prepared to obtain photocatalysts with higher photocatalytic efficiency, active under visible light and easy to removed from aqueous medium. TiO₂ powders were synthesized by the sol–gel method and modified using glucose and ammonium nitrate as source of C and N, respectively. Scanning electron microscope (SEM), X-ray diffraction (XRD), DRUV–Vis spectra and Raman techniques, were used to characterize the modified TiO₂ powders. The structural and physicochemical properties of the microbeads were analyzed by nitrogen physisorption, functional groups were identified by Fourier transform Infrared (FT-IR) spectroscopy and microbeads were observed by optical microscopy. The microbeads photocatalytic efficiency under visible light was evaluated monitoring the E. coli growth-inhibition, determined by colony count analysis (CFU—colony forming units). Results showed effectiveness in all tested composites to inhibit E. coli growth in 24 h under visible light. Furthermore chitosan microbeads with C,N-codoped TiO₂ showed the best performance in the degradation test being the most effective composite to achieving 99.99% of E. coli growth inhibition in less than 4 h.

制备了具有C掺杂的TiO ₂，N掺杂的TiO ₂和C，N掺杂的TiO _2的壳聚糖微珠，得到具有较高的光催化效率，在可见光下具有活性并且易于从水性介质中去除的光催化剂。TiO ₂粉末是通过溶胶-凝胶法合成的，并分别使用葡萄糖和硝酸铵作为C和N的来源进行了改性。扫描电子显微镜（SEM），X射线衍射（XRD），DRUV-Vis光谱和拉曼技术用于表征改性的TiO ₂粉末。通过氮的物理吸附分析微珠的结构和理化性质，通过傅立叶变换红外光谱（FT-IR）鉴定官能团，并通过光学显微镜观察微珠。通过监测菌落计数分析（CFU-菌落形成单位）来监测大肠杆菌的生长抑制情况，从而评估可见光下微珠的光催化效率。结果表明，所有测试的复合材料在可见光下均可在24小时内抑制大肠杆菌生长。此外，具有C，N掺杂的TiO _2的壳聚糖微珠在降解测试中显示出最佳性能，是实现99.99％大肠杆菌的最有效复合材料。 在不到4小时内抑制生长。