High-performance planar heterojunction perovskite solar cells: Preserving long charge carrier diffusion lengths and interfacial engineering
perovskite solar cells, planar heterojunction, charge carrier diffusion lengths, ZnO nanocrystal films, large area devices
We demonstrate that charge carrier diffusion lengths of two classes of perovskites, CH3NH3PbI3–xClx and CH3NH3PbI3, are both highly sensitive to film processing conditions and optimal processing procedures are critical to preserving the long carrier diffusion lengths of the perovskite films. This understanding, together with the improved cathode interface using bilayer-structured electron transporting interlayers of [6,6]-phenyl-C61-butyric acid methyl ester (PCBM)/ZnO, leads to the successful fabrication of highly efficient, stable and reproducible planar heterojunction CH3NH3PbI3–xClx solar cells with impressive power-conversion efficiencies (PCEs) up to 15.9%. A 1-square-centimeter device yielding a PCE of 12.3% has been realized, demonstrating that this simple planar structure is promising for large-area devices.
Tsinghua University Press
Sai Bai,Zhongwei Wu,Xiaojing Wu,Yizheng Jin,Ni Zhao,Zhihui Chen,Qingqing Mei,Xin Wang,Zhizhen Ye,Tao Song,Ruiyuan Liu,Shuit-tong Lee,Baoquan Sun, High-performance planar heterojunction perovskite solar cells: Preserving long charge carrier diffusion lengths and interfacial engineering. NanoRes.2014, 7(12): 1749–1758