| With the rise of the industrial revolution and the rapid development of the global industrialization, environmental pollution and resources shortage caused by energy consumption becomes more and more seriously. In recent decades, the researchers have been committed to environmentally friendly clean energy. Since1893, when the photovoltaic effect was found at the first time, solar energy has gradually become a hot research topic. At the moment, the United States, Janpan, Israel and other countries have already had a large number of solar-power installations, and how to improve the utilization of solar energy is always pursuited by the research scholars.At the same time, the consumption of the fuel oil etc. lead to the rapidly increase of the carbon dioxide emissions, which leads to the greenhouse effect and great affects the climate and environment on the earth. Degrading and transforming pollutants to the effective energy becomes the focus of the research topics. Among them, the reduction of carbon dioxide also attracts too much attention. At present, the carbon dioxide reduction is mainly converted to useful hydrocarbon fuel with water under the action of a catalyst and sunlight. In the existing semiconductor photocatalytic materials, titanium dioxide has been considered one of the most promising photocatalytic materials and has been widely studied, because of its nontoxic characteristics, cheap and stability.Although the photocatalytic performance of titanium dioxide was found by Fujishima and Honda as early as1972, and scientists have done a lot of researches to improve the photocatalytic properties and make a thorough inquiry to the reaction mechanism of titanium dioxide in the past forty years, titanium dioxide still can’t be widely usded in photocatasis according to its low photocatalytic eefficiency.On thebasis of the phtocatalysis theory of TiO2, this paper mainly synthesised TiO2nanorods by hydrothermal synthesis, then deposited Cu and Ag particles on the surface of the TiO2nanorod films by the electrochemical metheod, deposited Ag nanoparticles on the ITO by the double potential method, and studied the photocatalytic reduction of CO2converstion rate and reduction mechanism. The main contents are as follows:1. Using hydrothermal preparation of the same size, uniform distribution and single crystal anatase type titanium dioxide narorods, studying the effect of the reaction time, temperature and mole ratio on the morphology and structure of TiO2. When the reaction time was23h, the temperature was120℃, the volume ratio of tetrabuty titanate and hydrochloric acid was1:30, the ideal titanium dioxide nanorods could grow on the FTO glass as desired.2. Under the high volt, the pure TiO2show the better performance of photoreduction CO2to CH4than the same sample without charged by high volt. As the increasing of high volt between25KV and45KV, the more yield of CH4was produced by photoreduction CO2with TiO2photocatalyst.3. Using different electrochemical method to deposit Cu and Ag nanoparticles on the titanium dioxide nanorods respectively, using the test method such as XRD, XPS, SEM, and TEM and so on to analysis the composite TiO2, and then photoreducing CO2by the composite TiO2under UV irradiation. Results showed that different production conditions and methods can effect the distribution and morphology of the matal nanoparticles on the surface of the TiO2, and also significantly influenced the photocatalysis performance of catalysising CO2, which was obviously better than that of pure TiO2nanorods. By fluorescence spectrophotometer testing, it was found that there was a weak plasma resonance on the surface of the metal nanostructures, which was also referred to as the local surface plasma (LSP).4. This paper also introduced the electrochemical deposition of Ag nanoparticles on the ITO. Modifying the depositing voltage and the concentration of precursor solution was to change the morphology, size and distribution of Ag nanoparticles and also to affect their local surface plasma effect. At the same time, there followed the advantages of the electrochemical deposition:●The deposition temperature is low, which can be operated at the room temperature.●The bond between substrates and nanoparticles is strong and stable.●The particle size, distribution density and morphology can be controlled by deposition poetential, deposition time and the ratios of the precurse solution. (?) This method can be utilized in the large sample production.(?) The producing equipments are inexpensive, and the process is simply, easily operated and well repeatable. |
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