摘要
We demonstrate a controllable formation of grain boundary PbI_2 nanoplates passivated CH_3NH_3PbI_3 and CH_3NH_3PbI_2Br perovskites for high performance solar cells with up to 17.8% and 14.4% efficiencies, which are higher than the corresponding phase pure perovskite solar cells.The PbI_2 passivated planar perovskite films were facilely prepared via direct gas/solid reaction of hydrohalide deficient PbI_2·x HI/Br precursor with CH_3NH_2 gas.The amount of PbI_2 impurities can be controlled by adjusting the hydrohalide deficiency in the precursors.The crystal growth investigation suggested that the PbI_2 is highly like to form during the annealing crystallization process instead of existing in either the PbI_2·xH I/Br precursor films or as grown perovskite films.The PbI_2 with controllable amount locating at grain boundary could effectively passivate the perovskites with a longer PL lifetime and enhanced V_(oc).
We demonstrate a controllable formation of grain boundary PbI_2 nanoplates passivated CH_3NH_3PbI_3 and CH_3NH_3PbI_2Br perovskites for high performance solar cells with up to 17.8% and 14.4% efficiencies, which are higher than the corresponding phase pure perovskite solar cells.The PbI_2 passivated planar perovskite films were facilely prepared via direct gas/solid reaction of hydrohalide deficient PbI_2·x HI/Br precursor with CH_3NH_2 gas.The amount of PbI_2 impurities can be controlled by adjusting the hydrohalide deficiency in the precursors.The crystal growth investigation suggested that the PbI_2 is highly like to form during the annealing crystallization process instead of existing in either the PbI_2·xH I/Br precursor films or as grown perovskite films.The PbI_2 with controllable amount locating at grain boundary could effectively passivate the perovskites with a longer PL lifetime and enhanced V_(oc).
引文
[1]T.Zhang,N.Guo,G.Li,X.Qian,Y.Zhao,Nano Energy 2016,26,50.