Influence of Cl Incorporation in Perovskite Precursor on the Crystal Growth and Storage Stability of Perovskite Solar Cells.
Influence of Cl Incorporation in Perovskite Precursor on the Crystal Growth and Storage Stability of Perovskite Solar Cells.
复制标题
DOI：
10.1021/acsami.8b19390
复制
发表时间：
2019-01
影响因子：
9.5
通讯作者：
Hui Zhang;Y. Lv;Jinpei Wang;Huili Ma;Zhengyi Sun;Wei Huang
中科院分区：
文献类型：
--
作者：
Hui Zhang;Y. Lv;Jinpei Wang;Huili Ma;Zhengyi Sun;Wei Huang
基于有机-无机混合铅卤化物钙钛矿的太阳能电池由于其高性能和溶液工艺的可行性而非常有前途。钙钛矿成分的元素工程是获得高效稳定太阳能电池的高质量晶体的简单途径。有人发现，部分取代I-与Cl-在钙钛矿前体促进晶体生长，晶粒尺寸大于层厚度，并促进PbI 2的自钝化层的产生。而残留的Cl-离子被怀疑扩散到空穴传输层组成的无处不在的螺-OMeCl 2，形成高度结合的离子配对的Cl-与氧化态的螺-OMeCl 2导致电荷提取不足和严重的可逆性能下降。由于在晶格中Pb-Br键的产生，通过提高每个单元之间的结合能来增强相稳定性，因此Br-掺杂有效地缓解了这个问题。二元卤化物（Br-/Cl-）掺杂的钙钛矿导致20.2%的冠军功率转换效率，并具有改善的长期存储稳定性。
Solar cells based on organic-inorganic hybrid lead-halide perovskites are very promising because of their high performance and solution process feasibility. Elemental engineering on perovskite composition is a facile path to obtain high-quality crystals for efficient and stable solar cells. It was found that partially substituting I- with Cl- in the perovskite precursor promoted crystal growth, with the grain size larger than the layer thickness, and facilitated the generation of a self-passivation layer of PbI2. Whereas the residual Cl- ions were suspected to diffuse to the hole-transport layer consisting of ubiquitously spiro-OMeTAD, the formation of highly bounded ionic pairing of Cl- with the oxidized state of spiro-OMeTAD led to insufficient charge extraction and severely reversible performance degradation. This issue was effectively alleviated upon Br- doping owing to the generation of Pb-Br bonds in the lattice that strengthened the phase stability by improving the binding energy between each unit. The binary halide (Br-/Cl-)-doped perovskites resulted in a champion power conversion efficiency of 20.2% with improved long-term storage stability.