Solution Processing Of ?-? Sulfide Semiconductor Thin Films And The Research On Photoelectric Properties

With the development of social economy,the demand for energy is increasing,and the energy crisis is becoming more and more prominent.At the same time,due to the emission of polluting gases in the process of consumption of fossil fuels,global climate anomalies and environmental pollution are caused.In order to alleviate the above crisis,green renewable energy has been developed and applied to various areas.Among those renewable energy sources,photovoltaic power has developed rapidly in recent decades and is regarded as an inexhaustible source of green energy.However,compared with the traditional power generation method,the price of PV is still relatively very high.This is mainly due to the mainstream product on the market is still silicon-based solar cell.The purification cost of silicon materials is expensive,which makes the cost of solar cells high.In order to reduce the cost of PV,many new materials have been developed,such as binary cadmium telluride,quaternary copper indium gallium selenide,organic-inorganic hybrid perovskite thin film solar cells.But these materials either contain toxic elements or are unstable,making these solar cells difficult for large-scale applications in the future.Therefore,in order to reduce the cost of PV.it is necessary to continue to explore new materials for solar cells.In recent years,binary antimony sulfide has been regarded as a promising solar cell material.This material is not only stable but also not contain toxic and rare elements.Therefore,if the efficiency of the antimony sulfide solar cell can be increased,this will largely reduce the cost of PV.Although antimony sulfide solar cells have been made great progress in recent years,its efficiency is still low compared to other kinds of solar cells.Therefore,the topic of this thesis is to increase the efficiency of antimony sulfide solar cells.In this thesis,the preparation of antimony sulfide solar cells by solution method is taken as the starting point.And the factors that restrict the efficiency of antimony sulfide solar cells and the corresponding solutions are studied in details.At the same time,organic material is used as a hole transport layer in the structure of the current mainstream antimony sulfide solar cells.In the same time,the organic hole transport layer is unstable,which will seriously affect the stability of antimony sulfide solar cells.In order to solve this problem,we introduced inorganic vanadium pentoxide as a hole transport layer to instead the organic transport layer to improve the stability of the solar cells.In addition,since the binary antimony sulfide solar cells sulfide is a two-dimensional layered compound,the solar cell efficiency is limited by the orientation of the film.However,the suitable orientation is difficult to obtain by conventional solution method.Therefore,in order to expand the research system and develop more choices for solar cell materials,we prepared a ternary copper bismuth sulfide(Cu3BiS3)by solution method.Through the study of its photoelectric properties,it was found that it can be used as the absorption layer for the next generation of solar cells.The main research content of this thesis is divided into the following parts:The first part(Chapter 1)firstly,we introduce the development status of antimony sulfide solar cells at home and abroad,and the main experimental methods as well as the existing problems in the preparation of antimony sulfide solar cells.In the second part(Chapter 2),a high-quality antimony sulfide film was prepared through a two-step spin coating method for the first time.The preparation of the antimony sulfide film by this method is simple and convenient.It is important that the antimony sulfide film prepared by this method is relatively thin which pave the way for the development of tandem antimony sulfide solar cells.Since the antimony sulfide prepared by this method is thin,the efficiency is limited to some extent because of the low shut current density.In order to further improve the efficiency of the solar cells,we have prepared a high-quality antimony sulfide film by one-step spin coating method,which has significantly improved the efficiency.The third part(Chapter 3),In order to solve the problem of instability of antimony sulfide solar cells caused by the instability of the organic hole transport layer,we prepared the inorganic vanadium pentoxide by the solution method to replace the organic transport layer.This effectively improves the stability of the solar cell without significantly reducing the efficiency of the solar cell.This laid the foundation for the development of high-efficiency all-inorganic antimony sulfide solar cells.The fourth part(Chapter 4),In order to expand the solar cell material family,we conducted a basic study on ternary copper bismuth(Cu3BiS3).We first prepared mixed metal oxides by solution method and then prepared Cu3BiS3 by sulfurizing the metal oxides.By adopting different sulfurization methods,the phase transition law and the corresponding mechanism are revealed.It lays the foundation for the future research of this material.At the same time,through the study of its basic photoelectric properties,it is promising to be applicated in solar cells as an absorber layer material.