有机铅碘钙钛矿太阳电池结构优化及光电性能计算

Structure optimization and optoelectronical property calculation for organic lead iodine perovskite solar cells

甲胺铅碘(CH_(3)NH_(3)PbI_(3) MAPbI_(3))和甲脒铅碘(CH(NH_(2))_(2)PbI_(3) FAPbI_(3))是目前最常用于太阳电池研究的有机铅碘钙钛矿材料.对于层状结构的钙钛矿太阳电池来说,每层薄膜的光学性质和厚度都影响着电池的光电转换效率.本文利用光学导纳法和严格耦合波分析法计算了金属氧化物透明导电薄膜掺锡氧化铟(IIi_(2)O_(3):Sn)、掺氟氧化锡(SnO_(2):F;),TiO_(2),MAPbI_(3)和FAPbI_(3)的吸收率和透射率,分析了各层厚度以及器件结构对电池短路电流密度的影响.结果表明:对于FTO(ITO)/TiO_(2)/MAPbI_(3)结构,FTO薄膜的厚度在50—450 nm,ITO厚度在10—150 nm时对入射光波长在360—800 nm的平均透射率为85%,对于FTO(ITO)/TiO_(2)/FAPbI_(3)结构,FTO和ITO薄膜的厚度分别在50—250 nm和10—150 nm时对入射光波长在360—840 nm的平均透射率分别为81.6%和78%.在FTO和TiO_(2)最优厚度下,MAPbI_(3)和FAPbI_(3)的厚度从300—1000 nm变化时,对应太阳电池短路电流密度分别在21.9—23.7 mA·cm^(-2)和23.0—24.4 mA·cm^(-2)范围.本文的研究对于设计和制备高转换效率的钙钛矿太阳电池具有指导意义.

Methylamine lead iodide(CH3NH3PbI_(3) MAPbI_(3))and formamidine lead iodide(CH(NH_(2))_(2) PbI_(3) FAPbI_(3))are the most commonly used organic lead iodine perovskite materials for solar cell research.For the perovskite solar cell with a layered structure,the optical properties and thickness of each layer affect the photoelectric conversion efficiency of the cell.In this paper,the optical admittance method and rigorous coupled wave analysis method are used to calculate the absorptivities and transmittances of metal oxide transparent conductive films for tin-doped indium oxide(In_(2)O_(3):Sn),fluorine-doped tin oxide(SnO_(2):F),TiO_(2),MAPbI_(3) and FAPbI_(3).The influence of each layer thickness and device structure on the short-circuit current density of the cell are analyzed.It is shown that for the FTO(ITO)/TiO_(2)/MAPbI_(3) structure,when the thickness of the FTO film is 50-450 nm and the thickness of the ITO film is 10-150 nm,the average transmittance for the 360-800 nm wavelength light is 85%.For the FTO(ITO)/TiO_(2)/FAPbI_(3) structure,when the thickness of the FTO film and ITO film are 50-250 nm and 10-150 nm,respectively,the average values of the transmittance for the 360-840 nm wavelength light are 81.6% and 78%,respectively.Under the optimal thickness of FTO and TiO_(2),and the thickness of MAPbI_(3) and FAPbI_(3) are 300-1000 nm,the corresponding short-circuit current densities are in a range of 21.9-23.7 and 23.0-24.4 mA·cm-2,respectively.The band gap of MAPbI_(3) and FAPbI_(3) are 1.56 and 1.48 eV,for which the corresponding absorption cut-off wavelengths are 796 and 840 nm,respectively,indicating that FAPbI_(3) has a wider absorption spectrum than MAPbI_(3).In order to maximize the Jsc value of the organic lead iodine perovskite solar cell,the thickness range of each layer for MAPbI_(3) perovskite solar cell(FTO thickness is(80±50)nm,ITO thickness is less than 120 nm,MAPbI_(3) thicknessis 300-600 nm)and for FAPbI_(3) perovskite solar cell(FTO thickness is(120±50)nm,ITO thickness is less than 180 nm,FAPbI_(3) thickness is 300-600 nm)are given.The research results of this article have guiding significance in designing and preparing the perovskite solar cells with high conversion efficiency.