Application Of Cu₂O/AuNPs/Cu And RGO/CuS Composites In Light-assisted Microbial Fuel Cell Cathode

As an integrated technology to address energy generation and environmental bioremediation simultaneously,MFCs have drawn much attention in recent years.However,their practical application is heavily limited by their relatively low power density.Traditional microbial fuel cells only have the conversion of chemical energy to electrical energy.Because of solar energy in nature is inexhaustible,a light-assisted microbial fuel cell is constructed,which hopes to achieve double conversion of light energy and chemical energy to improve the power output of microbial fuel cells.The main contents are as follows:1.Application of 3D rGO/CuS composites in light-assisted microbial fuel cell cathodeTraditional microbial fuel cells only have the conversion of chemical energy to electric energy,Because of solar energy in nature is inexhaustible,a light-assisted microbial fuel cell is constructed,which adopts p-type semiconductor CuS with photoelectric conversion performance.The rGO/CuS composites formed by the onepot method is used to construct an electrode based on carbon paper,which is used as a photocathode of a light-assisted microbial fuel cell,and the performance is compared with that of bare carbon paper(CP)have increased by 42.1%,demonstrating the feasibility of multiple energy conversion strategies to improve microbial fuel cell performance.It was also found that the addition of rGO reduced the band gap of rGO/CuS,which was supposed to be caused by the chemical bond formed by both Cu and C by XPS test.2.Application of Cu2O/AuNPs/Cu nano-array materials in light-assisted microbial fuel cells cathodeLight-assisted microbial fuel cells can improve the performance of traditional microbial fuel cells,where the the photocathode directly affects the performance of the entire cell.In this work,the photoelectrocatalytic Cu2O/AuNPs/Cu nano arrays with higher photoelectric conversion efficiency was designed,which is based on the size of the photocatalyst,the contact between the cocatalyst and the photocatalyst,the contact area of the photocatalyst with the electron acceptor,and the light-receiving surface of the photocatalyst.Moreover,well-conducting copper foam as the supporting substrate and precursor is low-cost.Importantly,the preparation of Cu2O/Cu nano-array integrated photocathode is simple by electrochemical oxidation,and the AuNPs generates plasmon resonance effect under illumination,which will produce highenergyh hot electron.The high-energy hot electrons are transferred to the Cu2O conduction band,thereby reducing the photo-generated carrier recombination.The obtained Cu2O/AuNPs/Cu nano-array photocathode electrode was assembled into the cathode of the microbial fuel cell,and the traditional microbial fuel cell was constructed by Cu foam to perform MFCs performance test.The former maximum power density was increased by more than 350%compared with the latter.It is indicated that the Cu2O/AuNPs/Cu nano-array substrate integrated electrode exhibits excellent photoelectric conversion performance in light-assisted microbial fuel cells,and has great potential for building light-assisted microbial fuel cells.