Simultaneously Electrocatalytic Reduction of Carbon Dioxide and Oxidation of Phenol with MnO2 Nanoparticles Modified Electrodes

• Main Author: 楊昱庭
• Other Authors: Chiung- Fen Cheng
• Format: Others
• Language: zh-TW
• Published: 2018
• Online Access: http://ndltd.ncl.edu.tw/handle/ax289b

碩士 === 東海大學 === 環境科學與工程學系 === 106 === Anthropogenic emission of carbon dioxide lead to greenhouse effect, global warming and ocean acidification. Therefore, how to reduce the emission of CO2 and convert CO2 into more reduced chemical species have been holding special attractions for researchers. MnO2 possesses advantages of low cost, environmental friendliness and high catalytic activity toward electrochemical reduction so as to be widely used as electrocatalysts in the process. The objectives of this study were to synthesize effective electrodes base on MnO2 catalysts and then be used to electrochemically reduce CO2 into useful products and synthesize CNTs/CF used to anode and oxidize phenol. Firstly, α-MnO2, β-MnO2 and γ-MnO2 was prepared via hydrothermal method. Then, the conductive glass of ITO (indium tin oxide) and CNTs (carbon nanotubes) grown carbon fiber (CNTs/CF) were used to load alpha-MnO2 via spinning coating so as to synthesize the electrodes of α-MnO2/ITO,β-MnO2/ITO and γ-MnO2/ITO and used CVD to obtain CNTs/CF, then synthesized to α-MnO2/CNTs/CF β-MnO2/CNTs/CF and γ-MnO2/CNTs/CF. The final electrode products were obtained via calcination under 603K for 30 mins after spinning coating of MnO2. The physicochemical properties of obtained materials in this study were determined by TEM, SEM, XRD, CV and LSV. The electrochemical activity of obtained electrodes was conducted in saturated CO2 solution with the electrolyte of 0.1 M KHCO3. The main reduced compounds generated during the electrochemical reduction of CO2 and oxidation of phenol. The result show MnO2 electrode reduced of CO2 that main product of CO, H2, CH2O2, C2H2O4. It is obvious that the catalyst developed in this study has been effective to convert carbon dioxide into useful Chemicals and oxidation of phenol at the same time. Compared with other studies, the hydrogen yield of α-MnO2/CNTs /CF is proved to be that the electrode developed by this study has the potential of application and the anode can degrade phenol by 60-70%. Choosing the best reduction efficiency compared α-MnO2/CNTs /CF in different from KHCO3 concentration. It was found 0.1 M KHCO3 1.5 times reduced to hydrogen of 0.01 M KHCO3. Compare single or double chamber which is better redox reaction ,it was found that the film in the middle of the double chamber allowed the hydrogen ions to be transferred to cathode side to enhance the reduction effect.