摘要
Although perovskite solar cells(PSCs)have achieved encouraging efficiency,the photon loss at the substrate due to light reflection has not been well addressed.Light management is promising to reduce reflection loss and realize higher power conversion efficiency(PCE)of PSCs.Here,a bilayer antireflective coating(ARC)has been designed and coated onto the backside of the glass substrate of(FAPbI_(3))_(x)(MAPbBr_(3))_(1-x)PSCs to enhance photon harvesting and consequently the device efficiency.The bottom layer of the bilayer ARC is made from a silica polymer and the top layer is made from the mixture of hexamethyldisiloxane-modified mesoporous silica nanoparticles and a fluorinated silica polymer.By adjusting the refractive index and the film thickness of each layer according to a two-layer model,enhanced glass transmittance in a broadband wavelength range can be reached,with the maximum transmittance increasing from ca.90%to over 95%.With the bilayer ARC,the maximum short-circuit current density and PCE of(FAPbI_(3))_(x)(MAPbBr_(3))_(1-x)PSCs can be increased from 25.5 m A cm^(-2)and 22.7%to 26.5 mA cm^(-2)and 23.9%with negligible changes in fill factor and opencircuit voltage.This work presents a simple yet effective strategy to enhance the efficiency of solar cells employing bilayer antirefective coatings,which can be applied to other types of solar cells.
虽然钙钛矿太阳能电池效率的发展令人鼓舞,但是由于光反射造成的器件基底界面的光子损失等问题仍然没有解决.光管理是降低反射损失并提高器件效率的有效途径.因此,我们设计了双层减反膜以涂敷在(FAPbI_(3))_(x)(MAPbBr_(3))_(1-x)钙钛矿太阳能电池的玻璃基底外侧,以期达到增加光吸收和提高器件效率的目的.该研究中的减反膜底层由硅聚合物构成,上层由氟代硅聚合物和六甲基二硅氧烷/介孔二氧化硅纳米粒子复合而成.通过精确调控上下层的折射率及厚度,我们在宽波段范围内实现了玻璃基底透过率从最高约90%显著提升到95%.在电池器件的玻璃基底外侧溶液涂膜制备减反膜后,(FAPbI_(3))_(x)(MAPbBr_(3))_(1-x)钙钛矿太阳能电池在保持填充因子和开路电压不变的情况下,短路电流和效率分别从25.5 mA cm^(-2)和22.7%提高到26.5 mA cm^(-2)和23.9%.本研究提出了一种简单、高效的通过双层减反膜的光管理提高太阳能电池效率的方法,且此方法可拓展到其他类型太阳能电池体系.
基金
the Natural Science Foundation of Hubei Province(2019CFB575)
the National Natural Science Foundation of China(51861145101)。
