Reducing Saturation-Current Density to Realize High-Efficiency Low-Bandgap Mixed Tin-Lead Halide Perovskite Solar Cells
Reducing Saturation-Current Density to Realize High-Efficiency Low-Bandgap Mixed Tin-Lead Halide Perovskite Solar Cells
复制标题
DOI：
10.1002/aenm.201803135
复制
发表时间：
2019-01-17
影响因子：
27.8
通讯作者：
Yan, Yanfa
中科院分区：
文献类型：
--
作者：
Li, Chongwen;Song, Zhaoning;Yan, Yanfa
低禁带混合锡铅卤化物钙钛矿子电池的性能不理想一直是阻碍全钙钛矿叠层太阳能电池功率转换效率（PCE）进步的主要障碍之一。通过对暗电流密度和分布的分析，发现晶界电荷复合是限制低禁带混合型锡铅卤化物钙钛矿子电池性能的关键因素。进一步发现溴的掺入可以有效地钝化晶界，并使暗电流密度降低2 - 3个数量级。通过优化Br浓度，低带隙（1.272 eV）的混合锡铅卤化物钙钛矿太阳能电池的开路电压赤字低至0.384 V和填充因子高达75%。性能最佳的器械显示PCE> 19%。研究结果为进一步提高低禁带混合锡铅卤化物钙钛矿太阳电池的性能指明了重要方向。
The unsatisfactory performance of low-bandgap mixed tin (Sn)-lead (Pb) halide perovskite subcells has been one of the major obstacles hindering the progress of the power conversion efficiencies (PCEs) of all-perovskite tandem solar cells. By analyzing dark-current density and distribution, it is identified that charge recombination at grain boundaries is a key factor limiting the performance of low-bandgap mixed Sn-Pb halide perovskite subcells. It is further found that bromine (Br) incorporation can effectively passivate grain boundaries and lower the dark current density by two-three orders of magnitude. By optimizing the Br concentration, low-bandgap (1.272 eV) mixed Sn-Pb halide perovskite solar cells are fabricated with open-circuit voltage deficits as low as 0.384 V and fill factors as high as 75%. The best-performing device demonstrates a PCE of >19%. The results suggest an important direction for improving the performance of low-bandgap mixed Sn-Pb halide perovskite solar cells.