Hydrothermally Synthesizing Nanospheres Of Pd Loaded TiO₂ For Photocatalytically Reducing CO₂ In Isopropanol To Isopropyl Formate

By now, CO2 has became the biggest culprits of the greenhouse effect,its content in the air is also on the rise. In order to solve the environmental problem, this paper tries to find the method of photocatalytically reducing CO2. Compared with other methods, photocatalytic reduction method has many advantages. For example, the reaction can be conducted under atmospheric pressure, and using ultraviolet light or sunlight as the light source. We prepared the different photocatalysts through hydrothermal method and hot-solvent method. Using the prepared photocatalysts, we explored the yield increase of organic products from reduction of CO2 in methanol and isopropanol solution, and converted CO2 into more useful products of high value-added.The experiments mainly include the following content:We prepared Ti O2 photocatalyst through sol-gel method and characterized by analytical instruments, the results showed that the Ti O2 had a good morphology and good catalytic activity. Meanwhile we explored the impact of catalysts under different experimental conditions on the their performance.We also explored the method of microwave hydrothermal synthesis of Ti O2 nanotubes,by adjusting the addition amount of sodium hydroxide, controlling of p H and the regulating power to produce Ti O2 nanomaterials. The catalytic activities were tested in the methanol solvent.Using hot-solvent method and oleic acid as solvent, tetrabutyl titanate as titanium source,we synthesized rod-shaped Ti O2 nanomaterials. No matter the degree of crystallinities or the specific surface areas, their photocatalytic performances had been greatly improved in solvent of isopropyl alcohol and under irradiation of the UV lamp, product of formic acid isopropyl ester production was detected.Based on the hydrothermal synthesized velvet shape Ti O2 nano ball, we loaded different mole ratios of palladium to form Ti O2-Pd for photocatalytically reducing CO2 in isopropyl alcohol, which had a high catalytic activity, the isopropyl formate detected by Gas Chromatography generated more by hydrothermal method than that by hot-solvent, the highest yield was 276.6μmol/g.cat/h.On the basis of the subject, we also studied the combination of Ti O2 with some sulfur compounds, such as Ti O2-Ce2S3,Ti O2-Sn2S3.We did some corresponding photocatalytic activity research to the two complex.