Structural Design And Photoelectrochemical Performance Of The P-type Copper-based Semiconductor Materials

Semiconductor materials have been widely used in the field of solar cells and photoelectrochemistry to solve the energy crisis and environmental pollution that human society is facing currently,and have also been widely concerned by researchers.For different applications,the development of semiconductor materials with different characteristics is a key factor to further improve the conversion efficiencies of solar cells and the photoelectrochemical properties of semiconductor.In this thesis,the p-type Cu-based semiconductor materials are regarded as the research object with different structure design to explore its corresponding photoelectrochemical performance and photovoltaic property when used as hole transport layer,in order to obtain p-type semiconductor materials with stable inorganic hole transport layer and excellent photoelectrochemical properties and promote its application in the fields of solar cell and photoelectrochemical research.Detailed description of the research was presented as following:1.Research on the hole transport layer of CuSCN for perovskite solar cellsP-type CuSCN inorganic hole transport layer was prepared by spin coating method,through UV ultraviolet irradiation and the comprehensive control of preparation temperature,improving the quality of the crystallization of CuSCN films effectively,inhibiting the form of incomplete crystallization ravines,promoting the crystal quality of perovskite absorption layer,raising the open circuit voltage and fill factor of perovskite solar cell.Finally,as hole transport layer in perovskite solar cell,the optimized CuSCN film improves the photoelectric conversion efficiency by 4.57times compared with not optimized CuSCN film.2.Preparation of hydrogenated CuGaO2 material and study on its photoelectricchemical propertiesIn this paper,the powdery CuGaO₂?CGO?was successfully prepared by hydrothermal method and hydrogenated to improve its photoelectric chemical properties.The investigative results show that the hydrogenated CGO-180H sample has better charge transfer and transfer characteristics than the pure phase CGO sample.At the same time,hydrogenation also greatly enhanced the absorption of samples to the visible region.Hydrogenation can greatly increase the carrier concentration of the sample,increase the band potential and increase the band bending,and promote charge separation and transfer at the semiconductor/electrolyte interface.Thereby,the photocurrent density of CGO was greatly increased.the photocurrent density of CGO-180H is nearly 8 times higher than that of the pure phase CGO sample.3.Design of p-CuGaO2/n-CdS heterojunction and study on its photocatalytic performanceIn this paper,CuGaO₂ prepared by hydrothermal method was placed in the precursor solution of CdS,and the composite samples with the content ratio of CdS and CuGaO₂ as 1:0.5,1:1 and 1:2 were prepared.The investigative results show that:when the material content ratio of CdS and CuGaO₂ is 1:1,not only can the agglomeration phenomenon of CdS be effectively improved,but the particles of CdS can well support the formation of heterogeneous junction on the surface of the flake CuGaO₂ and promote the separation of photogenerated carrier electron hole pairs.A1:1 material ratio CuCaO₂/CdS heterojunction composite sample can effectively separate photogenerated charge and inhibit charge recombination,so that more photogenerated carriers can be transported to the semiconductor/electrolyte interface and participate in the redox reaction.Heterogeneous CuCaO₂/CdS complexes have the highest degradation rate,and the degradation performance of CuCaO₂/CdS has been improved by 91%compared with that of pure phase CdS.It has been proved that 1:1 heterogeneous CuCaO₂/CdS complexes have stronger ability of charge transmission and transfer.