Application And Research Of Interfacial Layer Materials In Antimony Chalcogenide Solar Cells

Due to the unique one-dimensional chain structure and excellent photovoltaic performance,antimony chalcogenides(Sb2X3,X=S,Se,S1-xSex)have broad application prospects in the field of photo voltaics.Over the years,the power conversion efficiency(PCE)of a single-junction solar cell with Sb2X3 as the absorber material has broken through the bottleneck of 10%.This has attracted more and more researchers’attention.However,large-scale development of this system of solar cells have been limited due to the inherent drawbacks of the interface-layer materials commonly used in high-performance Sb2X3 solar cells,such as the toxicity and narrow bandgap of CdS(electron transporting material,ETM),as well as high cost and low stability of SpiroOMeTAD(hole transporting material,HTM).In order to solve this problem,this thesis focuses on the ETM and HTM which are environmentally friendly and more promising metal oxide interface-layer materials,and introduce such ETM/HTM into the hydrothermal Sb2X3 solar cells,hoping to complete the substitution of CdS and SpiroOMeTAD in the future.The specific content of this paper is divided into the following five chapters:In chapter 1,the background of solar energy is introduced firstly,and then the development overview,basic principle and main performance parameters of solar cells are described.After that,the material properties of Sb2X3,the development of Sb2X3 solar cells and the application of interface materials in this solar cell system are clarified.Finally,the main research contents of this paper are put forward.In chapter 2,a brief induction of the preparation methods and characterization techniques of thin film and device involved in experiments is narrated.Besides,the equipment type and related parameters used in experiments are also briefly described.In chapter 3,Sb2(S,Se)3 thin film with high quality and preferential orientation of[hk1]were successfully prepared on nanoparticle TiO2 substrates by hydrothermal deposition.The growth mechanism of Sb2(S,Se)3 on the nanoparticle TiO2 and traditional compact TiO2 thin film substrates was analyzed by XRD,SEM and HRTEM.In addition,after J-V testing,it is found that the performance parameters of the nanoparticle TiO2 thin film ETM device are significantly improved compared with the traditional compact TiO2 ETM device,and the PCE of the best device reaches 7.08%,which is also the highest efficiency value of single-junction photovoltaic device with Sb2(S,Se)3 absorber layer prepared by hydrothermal deposition on TiO2.In chapter 4,the post annealing treatment of the MoO3 hole transport layer in the argon-oxygen mixture(5%O2)and the thickness of the MoO3 film deposited by vacuum evaporation were optimized.The all-inorganic Sb2S3 solar cell with a MoO3 hole layer has been successfully fabricated with a best PCE of 5.02%,which is also the highest efficiency value of Sb2S3 photovoltaic device with MoO3 as the HTM.Besides,it is found that the open circuit voltage of the MoO3 HTM device can be greatly improved by the argon-oxygen post-annealing treatment.In addition,XRD,SEM,XPS,UPS,fsTas,UV-vis-NIR and other characterization methods were used to analyze the mechanism of the performance changes of the film and device.In chapter 5,the main research results of this paper are summarized,and then the problems found in the process of experiment and analysis,such as the unstable device yield and the mismatch of the energy band structure of the MoO3 HTM device,are reflected.At the same time,the ideas and prospects for solving the problems are also put forward,in order to obtain Sb2X3 solar cell with better performance.