Cu/TiO2-NiO上光促表面催化CO2和H2O合成CH3OH反应规律

采用溶胶-凝胶法制备了n(电子型)-p(空穴型) 复合半导体材料0.5％Cu/TiO2-2.0％NiO (w),利用X射线衍射(XRD)、透射电镜(TEM)、红外光谱(IR)、紫外-可见光漫反射(UV-Vis)、程序升温脱附(TPD)技术对材料结构、吸光性能、化学吸附性能进行了表征,研究了该材料对CO2和H2O合成CH3OH的光促表面催化反应(PSSR)规律.结果表明,所制备材料能够明显促进目的反应,室温条件下即有CH3OH生成.在200 ℃下,由于光-表面-热的协同效应,CO2转化率得以提高,且CH3OH的选择性达到87.5％ .根据实验结果,得出CO2在材料表面的卧式吸附态为CH3OH的前驱物,并对PSSR机理进行了讨论.

The Photo Stimulated Surface Reaction of Synthesis of Methanol from Carbon Dioxide and Water on Cu/TiO2-NiO

The n-p coupled semiconductor material 0.5％Cu/TiO2-2.0％NiO was prepared using sol-gel method, on which the photo stimulated surface reaction (PSSR) of the synthesis of CH3OH from CO2 and H2O was studied. XRD, TEM, IR, UV-Vis and TPD experiments were adopted to characterizing the structure, photon absorbing and chemisorbing ability of the material. It was revealed that, during PSSR on the prepared material,CH3OH can be secured at normal temperature; while at the temperature of 200 ℃,CO2 conversion can be further increased, and the selectivity for CH3OH could reach up to 87.5％, because of the light-surface-heat cooperation effect. According to the experimental results, the surface precursor of CH3OH was specified to be the horizontal adsorbed state of CO2.Finally the PSSR mechanism was presented.