In perovskite solar cells(PSCs),the light-soaking effect,which means device performance changes obviously under continuous light illumination,is potentially harmful to loaded devices as well as accurately assessing th...In perovskite solar cells(PSCs),the light-soaking effect,which means device performance changes obviously under continuous light illumination,is potentially harmful to loaded devices as well as accurately assessing their efficiency.Herein,chemically stable tungsten trioxide(WO3)with high electron mobility is used as electron transport material in methylamine(MA)-free PSCs.However,the light-soaking effect is observed apparently in our devices.A fullerene derivative,C60 pyrrolidine Tris-acid(CPTA),is introduced to modify the interface between WO3 and perovskite(PVK)layers,which can bond with WO3 and PVK simultaneously,leading to the passivation of the defect and the suppression of trap-assisted nonradiative recombination.What is more,the introduction of CPTA can enhance the built-in electric field between WO3 and PVK layers,thereby facilitating the electron extraction and inhibiting the carrier accumulation at the interface.Consequently,the lightsoaking effect of WO3-based PSCs has been eliminated,and the power conversion efficiency has been boosted from 17.4%for control device to 20.5%for WO3/CPTA-based PSC with enhanced stability.This study gives guidance for the design of interfacial molecules to eliminate the light-soaking effect.展开更多
基金National Natural Science Foundation of China,Grant/Award Numbers:51925206,U1932214National Key Research and Development Program of China,Grant/Award Number:2017YFA0402800。
文摘In perovskite solar cells(PSCs),the light-soaking effect,which means device performance changes obviously under continuous light illumination,is potentially harmful to loaded devices as well as accurately assessing their efficiency.Herein,chemically stable tungsten trioxide(WO3)with high electron mobility is used as electron transport material in methylamine(MA)-free PSCs.However,the light-soaking effect is observed apparently in our devices.A fullerene derivative,C60 pyrrolidine Tris-acid(CPTA),is introduced to modify the interface between WO3 and perovskite(PVK)layers,which can bond with WO3 and PVK simultaneously,leading to the passivation of the defect and the suppression of trap-assisted nonradiative recombination.What is more,the introduction of CPTA can enhance the built-in electric field between WO3 and PVK layers,thereby facilitating the electron extraction and inhibiting the carrier accumulation at the interface.Consequently,the lightsoaking effect of WO3-based PSCs has been eliminated,and the power conversion efficiency has been boosted from 17.4%for control device to 20.5%for WO3/CPTA-based PSC with enhanced stability.This study gives guidance for the design of interfacial molecules to eliminate the light-soaking effect.
