Study Of CuPbSbS₃ Photoelectric Properties And Thin-Film Solar Cells

Solar cells are the devices that convert solar energy into electrical energy based on the photovoltaic effect.The clean and renewable energy is gradually becoming the future mainstream energy.Under such trend,solar cells have become the spotlight of research and development(R&D)due to their advantages of pollution-free and renewable and wide sources.Thin-film solar cells can fully absorb the incident light and convert it into electricity with film thickness of hundreds of nanometers or a few microns.As the crucial component of thin film solar cell,the light absorber has always been an important research topic.At present,the most successful absorber materials such as Cd Te,CIGS,and halide perovskites,despite exhibiting vast advantage for photovoltaic applications,still suffer from requirement of scarce elements or instability,thus restricting their further developments.Cuprous lead antimony trisulfide(CuPbSbS₃)is a natural semiconductor material with rich earth reserves.The previous research has confirmed that it owns stably physical and chemical properties and suitable optoelectronic properties.It is expected to show the possibility of application for thin-film solar cells.Based on this,this paper systematically studied the relevant properties of this semiconductor as a light-absorbing material for thin-film solar cells,and produced an efficient thin-film solar cell device for the first time.We first synthesized CuPbSbS₃ precursor via the butyldithiocarbamic acid(BDCA)solution method and fabriacte high-quality Cu Pb Sb S₃ film layer via spin coating.We then,based on experimental results,confirmed its direct band gap of 1.3 e V,high optical absorption coefficient and suitable band energy,which promise its application for thin-film solar cells.Using Cd S as the electron transport layer(ETL),we fabricated a photovoltaic device with glass/ITO/Cd S/Cu Pb Sb S₃/Spiro-OMe TAD/Au configuration and achieved a power conversion efficiency(PCE)of 2.23%and open-circuit voltage(V_OC)of 699 m V after preliminary optimization.In order to further improve device performance,a stable,non-toxic and wide bandgap Ti O₂ is selected as the ETL to substitute previously employed Cd S ETL.We imporved Cu Pb Sb S₃ film crystallinity and charge collection efficiency by adjusting annealing temperature,reducing carbon residue,decreasing precursor viscosity,and ultilizing ethanol cleaning.Conseqently,our devices,with the structure of glass/FTO/Ti O₂/Cu Pb Sb S₃/Spiro-OMe TAD/Au,obtained a higher PCE of 2.65%and higher short-circuit current density(J_SC)of 12.4 m A/cm².Furthermore,our Cu Pb Sb S₃ thin film solar cells could maintain a high level of performance(PCE>80%)after placing in air for 1 month without encapsulation,showcasing its good device stability.