Research On Cu₂ZnSnS₄ Photovoltaic Material And MoS₂ Lateral Homojunction Solar Cells

Cu₂Zn Sn S₄（CZTS）compound is a substitution for Cu（In,Ga）Se₂ as an absorbing layer in solar cells.It has similar structure and photovoltaic effect compared to CIGS,while the component of CZTS is abundant and non-toxic,making it a promising candidate for photovoltaic application.Developing a both economical and efficient preparation process is the foundation for realizeing the industrial production of CZTS photovoltaic material.To date,non-vacuum deposition processing is one of the most promising methods,and the conversion condition during sulfurization is the key factor of the quality of the thin film.In this research,CZTS precursor solution was prepared by ball milling method,in order to optimize the condition of sulfurization,the precursor thin films sulfurized under different conditions were studied after deposition.The effect of parameters such as sulfur mass,composition of ambient gas,pressure of ambient gas,dwelling time,heating and cooling mode on the phase and morphology of the thin film were studied.The results showed the optimal condition is to offer 150 mg of sulfur during sulfurization,heating fast to reaction temperature,being sulfurized in 25 k Pa H₂/N₂ for 30min and then cooling naturally.MoS₂ is the representation of two-dimensional material transition metal dichalcogenides（TMDCs）.The adjustable bandgap,high absorption coefficient per unit thickness as well as excellent optical and electrical properties,making it an ideal material to the application of next generation soalr cells.The basic structure of a solar cell is p-n junction,whose interface is significant to the performance of the device.In this research,CVD grown n-type MoS₂ was p-doped by nitrogen plasma controlled by toroidal magnetic field（TMF）,charecterizations such as Raman and PL spectra were carried out to identify the p-type doping effect.Meanwhile,MoS₂ lateral p-n homojunction solar cell was fabricated by area selective nitrogen plasma doping,the I-V characteristics of the homojunction were investigated and a typical rectifying effect was exhibited.Under AM1.5G illumination,the solar cell displayed photovoltaic properties.