中文摘要：

用不同温度控制分解草酸氧钛铵制备N掺杂TiO2光催化剂．利用XRD、IR、热分析、N2吸-脱附等温线、XPS、紫外可见漫反射光谱和SEM表征了N-TiO2光催化剂的结构．400～600 ℃焙烧的N-TiO2光催化剂为纯锐钛矿相，而700 ℃焙烧的N-TiO2光催化剂为锐钛矿和金红石混合相．N掺杂在TiO2的间隙位使锐钛矿相TiO2带隙变窄．在光降解甲基橙的反应中，600和400 ℃焙烧的N-TiO2催化剂分别在紫外光和全波长光照射下有最好活性；700 ℃焙烧的N-TiO2催化剂无论在紫外光和全波长光下都表现出最好的比活性，即最高的光量子效率，这可以归因于700℃焙烧的N-TiO2光催化剂良好的结晶程度和锐钛矿-金红石异相结的存在．

英文摘要：

We developed a novel approach for the preparation of N-doped TiO2 photocatalysts by calcining ammonium titanium oxalate at different temperatures. The structures of N-TiO2 were characterized by powder X-ray diffraction, infrared spectroscopy, thermogravimetric analysis, N2 adsorption-desorption isotherms, X-ray photoelectron spectroscopy, diffuse reflectance UV-Vis spectroscopy, and scanning electron microscope. The N-doped TiO2 photocatalysts calcined below 700 ℃ are the pure anatase phase but that calcined at 700 ℃ is a mixture of anatase and rutile phases. The doped N locates at the interstitial site of TiO2 which leads to the narrowing of bad gap of pure anatase N-TiO2. Among all photocatalysts, N-TiO2 photocatalysts calcined at 600 and 400 ℃ exhibit the best performance in the photodegradation of methyl orange under the UV light and all-wavelength light illuminations, respectively; however, because of the perfect crystallinity and the existence of anatase-rutile phase junctions, N-TiO2 photocatalyst calcined at 700 ℃ exhibits the highest specific photodegradation rate, i.e., the highest quantum yield, under both the UV light and all-wavelength light illuminations.