Highly crystalline perovskite films with large grains and few grain boundaries are conducive for efficient and stable perovskite solar cells.Current methods for preparing perovskite films are mostly based on a fast cr...Highly crystalline perovskite films with large grains and few grain boundaries are conducive for efficient and stable perovskite solar cells.Current methods for preparing perovskite films are mostly based on a fast crystallization process,with rapid nucleation and insufficient growth.In this study,MAPbI3 perovskite with inhibited nucleation and promoted growth in the TiO_(2)/ZrO_(2)/carbon triple mesoscopic scaffold was crystallized by modulating the precursor and the crystallization process.N-methylformamide showed high solubility for both methylammonium iodide and Pbl2 and hampered the formation of large colloids in the MAPbI3 precursor solution.Furthermore,methylammonium chloride was added to reduce large colloids,which are a possible source of nucleation sites.During the crystallization of MAPbI3,the solvent was removed at a slow controlled speed,to avoid rapid nucleation and provide sufficient time for crystal growth.As a result,highly oriented MAPbI3 crystals with suppressed non-radiative recombination and promoted charge transport were obtained in the triple mesoscopic layer with disordered pores.The corresponding hole-conductor-free,printable mesoscopic perovskite solar cells exhibited a highest power conversion efficiency of 18.82%.The device also exhibited promising long-term operational sta-bility of 1000 h under continuous illumination at maximum power point at 55±5°C and damp-heat stability of 1340 h aging at 85°C as well as 85%relative humidity.展开更多
基金The authors acknowledge financial support from the National Natural Science Foundation of China(Grants No.91733301,51902117,52172198,and 22075094)the Fundamental Research Funds for the Central Universities,the Science and Technology Department of Hubei Province(Grant No.2017AAA190)+1 种基金the 111 Project(Grant No.B07038),the Program for HUST Academic Frontier Youth Team(Grant No.2016QYTD06)the Fundamental Research Funds for the Central Universities(Grant No.2019kfyXJJS051).
文摘Highly crystalline perovskite films with large grains and few grain boundaries are conducive for efficient and stable perovskite solar cells.Current methods for preparing perovskite films are mostly based on a fast crystallization process,with rapid nucleation and insufficient growth.In this study,MAPbI3 perovskite with inhibited nucleation and promoted growth in the TiO_(2)/ZrO_(2)/carbon triple mesoscopic scaffold was crystallized by modulating the precursor and the crystallization process.N-methylformamide showed high solubility for both methylammonium iodide and Pbl2 and hampered the formation of large colloids in the MAPbI3 precursor solution.Furthermore,methylammonium chloride was added to reduce large colloids,which are a possible source of nucleation sites.During the crystallization of MAPbI3,the solvent was removed at a slow controlled speed,to avoid rapid nucleation and provide sufficient time for crystal growth.As a result,highly oriented MAPbI3 crystals with suppressed non-radiative recombination and promoted charge transport were obtained in the triple mesoscopic layer with disordered pores.The corresponding hole-conductor-free,printable mesoscopic perovskite solar cells exhibited a highest power conversion efficiency of 18.82%.The device also exhibited promising long-term operational sta-bility of 1000 h under continuous illumination at maximum power point at 55±5°C and damp-heat stability of 1340 h aging at 85°C as well as 85%relative humidity.
