Study On Preparation And Performance Of ZnS Buffer Layer Materials For Copper-Based Thin-Film Solar Cells

Copper indium gallium selenide（Cu（In,Ga）Se₂,referred to as CIGS）thin-film solar cells have strong stability and high photoelectric conversion efficiency（23.35%）.Cadmium sulfide（Cd S）is commonly used as a buffer layer in CIGS thin-film solar cells with high conversion efficiency.However,the Cd S material itself is toxic,pollutes the environment,and the cut-off wavelength loses a large amount of incident light.For this reason,we use zinc sulfide（Zn S）,which is more environmentally friendly and has a wider band gap,instead of Cd S as the buffer layer.Through the Zn S/CIGS energy band structure,it is found that pure Zn S easily causes the electron transmission barrier to be too high,and it is easy to cause the battery to disconnect.The investigation found that Zn（O,S）prepared by doping O in Zn S is more suitable as a buffer layer material.Comparing the preparation of traditional CBD-Zn（O,S）and CBD-Cd（O,S）buffer layers,it is found that the preparation time of CBD-Zn（O,S）is longer than CBD-Cd（O,S）buffer layers,and too long deposition time will deteriorate the overall performance of the battery.Research on the deposition rate of CBD-Zn（O,S）.In this essay,zinc sulfate（Zn SO₄）,ammonia（NH₄OH）/trisodium nitrilotriacetate（Na₃NTA）mixed complexing agent and thioacetamide（TAA）with a faster hydrolysis rate are selected as a new system for water bath deposition of Zn（O,S）Research.Combining coordination balance and precipitation balance,a detailed study and derivation of the formula for calculating the content of each complex ion during the complexing process,the introduction of Medusa software to assist in simulating the changes in the concentration of different reactants and the p H value and other variables for the content and distribution of each complex ion.The composition of the reaction precursor and the control of the ratio,the process conditions,and the effects of annealing on the Zn（O,S）film were studied.When Zn SO₄=0.04 M,NH₄OH=0.48 M,Na₃NTA=0.04 M,TAA=0.05 M,p H=10,water bath temperature of 80℃,deposition time of 15 min,and rotation speed of 360 r/min.Based on the Zn（O,S）buffer layer,the efficiency of CIGS thin-film battery devices is 12.5%.