摘要
The development of organometal halide perovskite solar cells has grown rapidly and the highest efficiency of the devices has recently surpassed 22%.Since these solar cells contain toxic lead, a sustainable strategy is required to prevent environmental pollution and avoid healthy hazard caused by possible lead outflow.Here, in situ recycling PbI_2 from thermal decomposition CH_3NH_3PbI_3 perovskite films for efficient perovskite solar cells was developed.The thermal behavior of CH_3NH_3PbI_3 perovskite and its individual components were examined by thermogravimetric analysis.By optimizing the process of thermal decomposition CH_3NH_3PbI_3 film, the completely conversion from CH_3NH_3PbI_3 to pure PbI_2 layer with a mesoporous scaffold was achieved.Conversely, the mesoporous PbI_2 structure readily enhances the conversion efficiency of perovskite film, and consequently transits to high-performance device.A perovskite crystal growth mechanism on the mesoporous PbI_2 structure was proposed based on the different TiO_2 nanostructures.These results suggest that the in situ recycled PbI_2 scaffolds can be a new route in manipulating the morphology of the perovskite active layer, providing new possibilities for high device performance.Meanwhile, the risk of lead outflow can be released while the recycled PbI_2 as the starting material for the sample and saving-energy fabrication of efficient solar cells can be realized.
The development of organometal halide perovskite solar cells has grown rapidly and the highest efficiency of the devices has recently surpassed 22%.Since these solar cells contain toxic lead, a sustainable strategy is required to prevent environmental pollution and avoid healthy hazard caused by possible lead outflow.Here, in situ recycling PbI_2 from thermal decomposition CH_3NH_3PbI_3 perovskite films for efficient perovskite solar cells was developed.The thermal behavior of CH_3NH_3PbI_3 perovskite and its individual components were examined by thermogravimetric analysis.By optimizing the process of thermal decomposition CH_3NH_3PbI_3 film, the completely conversion from CH_3NH_3PbI_3 to pure PbI_2 layer with a mesoporous scaffold was achieved.Conversely, the mesoporous PbI_2 structure readily enhances the conversion efficiency of perovskite film, and consequently transits to high-performance device.A perovskite crystal growth mechanism on the mesoporous PbI_2 structure was proposed based on the different TiO_2 nanostructures.These results suggest that the in situ recycled PbI_2 scaffolds can be a new route in manipulating the morphology of the perovskite active layer, providing new possibilities for high device performance.Meanwhile, the risk of lead outflow can be released while the recycled PbI_2 as the starting material for the sample and saving-energy fabrication of efficient solar cells can be realized.
引文