采用溶胶-凝胶法和溶胶-乳化-燃烧法制备了Sm3+/TiO2光催化剂,并用X射线衍射(XRD)、透射电镜(TEM)、紫外可见吸收光谱(UV-Vis)、红外光谱(IR)等分析技术表征了催化剂,考察了制备方法、离子掺杂量等对催化剂光催化还原CO2和H2O合成CH3OH实验的影响.实验结果表明,掺杂后的催化剂颗粒更均匀,比表面相应增加,溶胶-乳化-燃烧法制备的催化剂晶粒更小,比表面积更大,光催化活性更高. The Sm3 + / TiO2 photocatalysts were prepared by sol-gel method and sol-emulsion-combustion method. The photocatalysts were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), UV-Vis, The effects of preparation method, ionic doping amount and other factors on the CH3OH synthesis by photocatalytic reduction of CO2 and H2O were investigated. The experimental results showed that the doped catalyst particles were more uniform and the specific surface area increased accordingly. The sol - emulsification - combustion catalyst prepared smaller grains, larger specific surface area, higher photocatalytic activity.