目的 采用溶液前驱体等离子喷涂制备TiO2以及Si掺杂TiO2涂层，并分别研究H2流量和Si掺杂对TiO2涂层光催化性能的影响。方法 通过X射线衍射、扫描电子显微镜、拉曼光谱和傅里叶变换近红外光谱表征样品的晶相、表面形貌以及化学结构，然后以甲基橙为目标物，借此模拟有机污染物，利用光化学反应仪测试TiO2以及Si掺杂TiO2涂层的光催化性能。结果 适量Si掺杂可以细化晶粒，提升TiO2涂层中锐钛相含量（从7.4%提高到49%），同时形成Ti—O—Si键，Si掺TiO2涂层甲基橙的降解率达到95%左右，高于纯TiO2涂层80%的降解率。随着H2流量增加，TiO2涂层中的晶粒明显粗化，主要以金红石相的形式存在，H2流量为8 L/min的TiO2涂层甲基橙降解率达到82%，要远高于H2流量为4、10 L/min的52%和33%。结论 Si掺杂TiO2涂层比纯TiO2涂层的光催化性能更优，当H2流量为8 L/min时，光催化性能最好。

The work aims to prepare TiO2 and Si-doped TiO2 coatings by solution precursor plasma spraying and respectively investigate effects of H2 flow and Si doping on photocatalytic performance of TiO2 coatings. The crystal phase, surface morphology and chemical structure of the samples were characterized by X-ray diffraction, scanning electron microscopy, Raman spectroscopy and Fourier transform near-infrared spectroscopy. The photocatalytic performance of TiO2 and Si doped TiO2 coatings was tested with photochemical reactor by using methyl orange as the target compound to simulate organic pollution. Appropriate amount of doped Si could refine the grains, increase the content of anatase phase in TiO2 coating (from 7.4% to 49%) and form Ti—O—Si bonds. The degradation rate of Si doped TiO2 coatings was up to 95% and higher than that of pure TiO2 coating as 80%. With the increase of hydrogen flow rate, the crystal grains of TiO2 coating obviously roughened and mainly existed in the form of rutile phase. The degradation rate of methyl orange in TiO2 coating with hydrogen flow rate of 8 L/min reached 82% which was much higher than 52% and 33% for hydrogen flow rate of 4 and 10 L/min. The photocatalytic performance of Si-doped TiO2 coating is better than that of pure TiO2 coating. The photocatalytic performance is the best when the hydrogen flow rate is 8 L/min.