Photocatalytic Fuel Cell Based On Titanium Dioxide Photoanode And Its Application In Water Treatment

With the increase of population and the acceleration of industrialization and urbanization,various organic wastewater has been discharged in large quantities,which has seriously affected human health and the ecological balance of the earth.Therefore,the treatment of water pollution has become an urgent problem in environment.Semiconductor photocatalytic technology has the advantages of strong oxidation ability,no secondary pollution,low energy consumption and relatively mild reaction conditions.Photocatalytic fuel cell combines photoanode and cathode supported photocatalyst to realize the purpose of recovering energy while degrading sewage,which has an essential research value.Bidoped TiO₂ photocatalysis material were synthesised through simple sol gel method.With SEM,XRD and XPS to explore the mechanism of doping and mechanism,confirmed the molar ratio of 3%for the best of the precursor solution doping ratio.Degradation rate of 91%and 10.2?A to obtain maximum photocurrent with Bi-3,by XPS confirmed the existence of the high oxidation state of Bi,reveals the photocatalytic performance improvement and optimum doping ratio is the cause of the introduction of A Bi high state of Bi^?3+??+to delay the composite of e^--h⁺.However,excessive amount of Bi³⁺introduced by excessive doping amount will have a negative effect as a new e^--h⁺complex center.The photocatalyst was successfully loaded onto the FTO electrode by screen printing method,and the photoanode was combined with Pt sheet to form PFC.The photocatalytic performance was consistent with the trend of powder state,which proved that the use of screen printing method would not change the performance of the photocatalyst.The PFC photoanode prepared by this method is not easy to fall off.After repeated three times,the maximum efficiency of photocatalysis is reduced by only 2%.The influence of the preparation process of TNAs photoanode on its morphology and structure was explored,and the positive correlation between the electrolysis time and TNAs tube length was confirmed by FESEM.The longer electrolysis,the longer of the TNAs.The longest length were 2?m.Its photocatalytic effect increases with the length of catalyst.The element structure and composition of the photocatalyst were verified by XRD and XPS,and the TNAs prepared by this method were proved to be anatase TiO₂ with intact and pure crystal.TNAs-Cu₂O has strong conductivity and photocurrent is significantly better than Bi-TiO₂ under the same area.In addition,TNAs-Cu₂O shows good synergistic effect,which confirms that the intrinsic bias improves the photocatalytic performance wih1.3 times higher than that of unipolar TNAs under the same condition.The relationship between photocurrent of PFC and COD was studied,and a method for monitoring COD in PFC by photocatalytic fuel cell was introduced.The model of this method was verified by two PFC electrode systems,and the quantitative relationship between photocurrent and COD was successfully established.When the fuel in the PFC system is at a relatively high concentration,the theoretical value presented by the quantitative relationship has a good correlation with the actual value.With the decrease of fuel concentration,the correlation becomes worse with the decrease of mass transfer..