物理化学学报2022，Vol.38Issue(4)：18-27,10.DOI:10.3866/PKU.WHXB202005007
湿空气下制备稳定的CsPbl2Br钙钛矿太阳电池
Fabrication of Stable CsPbl2Br Perovskite Solar Cells in the Humid Air
摘要
Abstract
Inorganic perovskite materials have gained considerable attention owing to their good thermal stability,high absorption coefficient,adjustable bandgap,and simple preparation.However,most inorganic perovskites are sensitive to water and need to be prepared under inert environments in a glove box,which increases their preparation cost.In this study,we used a simple one-step spin coating anti-solvent process to prepare CsPbl2Br,which was then annealed in humid air(relative humidity＜35％)at 300℃for 5 min with isopropanol as the anti-solvent.An inorganic perovskite solar cell with fluorine-doped tin dioxide/compact TiO2/mesoporous TiO2/CsPbl2Br/hole transport materials/Ag structure was prepared.By varying the concentration of the mesoporous precursor,we controlled the thickness of mesoporous TiO2 in order to investigate its effect on the properties of the perovskite films and devices.The X-ray diffraction(XRD)results confirmed the successful synthesis of CsPbl2Br in humid air.Moreover,the thickness of the substrate affected the crystal growth orientation.The scanning electron microscopy results revealed that the thickness of the mesoporous titanium dioxide substrate affected the crystallization processing of CsPbl2Br,resulting in the formation of compounds with different morphologies and phases.The ultraviolet-visible(UV-Vis)and photoluminescence spectra of the perovskite materials revealed that the substrate thickness affected their optical properties.With a decrease in the thickness of the mesoporous TiO2 substrate,the bandgap of CsPbl2Br increased slightly.At the substrate thickness of 145 nm,the defect density of state of CsPbl2Br increased.At the optimum mesoporous titanium dioxide substrate thickness of 732 nm,the device showed the best power conversion efficiency of 8.16％.The electrochemical impedance spectroscopy measurements revealed that the devices prepared on thicker mesoporous layers showed better carrier extraction and transmission capabilities but higher interfacial charge recombination resistance,leading to a lower open-circuit voltage but higher current density.Thus,an increase in the thickness of the mesoporous substrate improved the photovoltaic performance of the devices.The stability of the CsPbl2Br perovskite film improved with an increase in the mesoporous substrate thickness.The stability test results along with the UV-Vis and XRD analysis results showed that the perovskite film prepared on the 732 nm-thick substrate showed no significant structure change after being placed in humid air for 144 h.The stability of the perovskite solar cells was also investigated.The device with the 732 nm-thick substrate could maintain its original efficiency of 73％after exposure to air with relative humidity less than 35％for 72 h.Thus,inorganic perovskite solar cells could be successfully prepared in the humid air environment.关键词
无机钙钛矿/太阳能电池/介孔层厚度/稳定性/湿空气制备Key words
Inorganic perovskite/Solar cell/Mesoporous layer thickness/Stability/Humid air preparation分类
化学化工引用本文复制引用
林飞宇,杨英,朱从潭,陈甜,马书鹏,罗媛,朱刘,郭学益..湿空气下制备稳定的CsPbl2Br钙钛矿太阳电池[J].物理化学学报,2022,38(4):18-27,10.基金项目
The project was supported by the National Natural Science Foundation of China(61774169)and the Fundamental Research Funds for the Central South University,China(2019zzts944,502211922).国家自然科学基金(61774169),中南大学自由探索创新项目(2019zzts944,502211922)资助 （61774169）
