以氮气为氮源、氢气为放电气体，利用介质阻挡放电（DBD）等离子体成功制备了N掺杂缺陷二氧化钛材料，并通过TEM、XPS、EDS和FT-IR等表征方法对其进行分析。结果表明，改性后的二氧化钛在80 min内光催化降解亚甲基蓝溶液可达96%，光催化降解速率约为未经处理二氧化钛的3.5倍。经过4次重复使用后，光催化性能仍能达到80%。经过DBD等离子体处理后的二氧化钛材料形成了氧空位和N掺杂，氧空位能在导带下形成缺陷能级，N掺杂能够在价带上形成杂质能级，在两者协同作用下，禁带宽度从3.2 eV减小至2.88 eV，增强了可见光区域的吸收。同时，光生电子-空穴复合速率受到抑制，产生更多的羟基自由基，从而提高二氧化钛的光催化活性。

A N-doped defective TiO₂ material is successfully prepared by means of dielectric barrier discharge (DBD) plasma with nitrogen as nitrogen source and hydrogen as discharge gas.The material is characterized by TEM, XPS, EDS, and FT-IR.Experimental results show that the photocatalytic degradation of methylene blue solution by the modified TiO₂ can reach 96% within 80 min, and the photocatalytic degradation rate is about 3.5 times that by the untreated TiO₂.Additionally, the photocatalytic performance of N-doped defective TiO₂ material can reach 80% after 4 cycles of repeated use.The characterization results show that oxygen vacancies and N-doping are formed in TiO₂ material after DBD plasma treatment.Oxygen vacancies can form defect levels under the conduction band, and N-doping can form impurity levels in the valence band.Under the synergistic effect between oxygen vacancies and N-doping, the forbidden band width is reduced from 3.0 eV to 2.88 eV, which enhances the absorption in visible light region.Meanwhile, the recombination rate of photogenerated electron-hole is inhibited, which can generate more hydroxyl radicals.Therefore, the catalytic activity of TiO₂ is improved.

张国平(1993-),男,硕士研究生,研究方向为光催化降解有机污染物,863288864@qq.com。