摘要
The energy barrier at the CH3NH3Pb Br3/TiO2interface hinders the electron transfer from CH3NH3Pb Br3to compact TiO2（cp-TiO2）.Ionic liquid（IL）,that forms dipoles pointing away from TiO2,can adjust the work function of TiO2resulting in suitable energy level for charge transfer from CH3NH3Pb Br3to TiO2.The time-resolved photoluminescence spectroscopy（TRPL）measurements confirm faster electron transfer from the CH3NH3Pb Br3film to TiO2after modification by IL.Solar cells based on IL modified cp-TiO2demonstrate efficiency of～6%,much higher than the devices（0.2%）fabricated using untreated cp-TiO2as the electron transport layer.
The energy barrier at the CH3NH3Pb Br3/TiO2interface hinders the electron transfer from CH3NH3Pb Br3to compact TiO2（cp-TiO2）.Ionic liquid（IL）,that forms dipoles pointing away from TiO2,can adjust the work function of TiO2resulting in suitable energy level for charge transfer from CH3NH3Pb Br3to TiO2.The time-resolved photoluminescence spectroscopy（TRPL）measurements confirm faster electron transfer from the CH3NH3Pb Br3film to TiO2after modification by IL.Solar cells based on IL modified cp-TiO2demonstrate efficiency of～6%,much higher than the devices（0.2%）fabricated using untreated cp-TiO2as the electron transport layer.
基金
the financial support from the Institute for Critical Technology and Applied Science(ICTAS)
the financial support from Office of Naval Research(I.Perez)through grant number N000141613043
the supports of National Natural Science Foundation of China under grant no.61604152
