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
The complete elimination of methylammonium(MA)cations in Sn-Pb composites can extend their light and thermal stabilities.Unfortunately,MA-free Sn-Pb alloyed perovskite thin films suffer from wrinkled surfaces and poor...The complete elimination of methylammonium(MA)cations in Sn-Pb composites can extend their light and thermal stabilities.Unfortunately,MA-free Sn-Pb alloyed perovskite thin films suffer from wrinkled surfaces and poor crystallization,due to the coexistence of mixed intermediate phases.Here,we report an additive strategy for finely regulating the impurities in the intermediate phase of Cs_(0.25)FA_(0.75)Pb_(0.6)Sn_(0.4)I_(3)and,thereby,obtaining high-performance solar cells.We introduced d-homoserine lactone hydrochloride(D-HLH)to form hydrogen bonds and strong Pb-O/Sn-O bonds with perovskite precursors,thereby weakening the incomplete complexation effect between polar aprotic solvents(e.g.,DMSO)and organic(FAI)or inorganic(CsI,PbI_(2),and SnI_(2))components,and balancing their nucleation processes.This treatment completely transformed mixed intermediate phases into pure preformed perovskite nuclei prior to thermal anneal-ing.Besides,this D-HLH substantially inhibited the oxidation of Sn^(2+) species.This strategy generated a record efficiency of 21.61%,with a Voc of 0.88 V for an MA-free Sn-Pb device,and an efficiency of 23.82%for its tandem device.The unencapsulated devices displayed impressive thermal stability at 85℃ for 300 h and much improved continuous operation stability at MPP for 120 h.展开更多
Changes of surface shape, aggregate state, and microstructure of Apocynum fiber before and after irradia-tion were studied by XRD, IR, SEM, ESR, and solid state 13C CP/ MAS NMR. The results show that the surface shape...Changes of surface shape, aggregate state, and microstructure of Apocynum fiber before and after irradia-tion were studied by XRD, IR, SEM, ESR, and solid state 13C CP/ MAS NMR. The results show that the surface shape and microstructure were not spoiled under 50 kGy gamma irradiation, while the crystallization of Apocynum fiber changed under 280 kGy . It also shows that different free radicals appear after irradiation and their concentration increases with the increase of irradiation dose.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.
基金funded by the Natural Science Foundation of Shanghai(22ZR1428200)the National Natural Science Foundation of China(51950410581)+1 种基金the Shanghai Government(20JC141500)and CATL-SJTU joint funding.
文摘The complete elimination of methylammonium(MA)cations in Sn-Pb composites can extend their light and thermal stabilities.Unfortunately,MA-free Sn-Pb alloyed perovskite thin films suffer from wrinkled surfaces and poor crystallization,due to the coexistence of mixed intermediate phases.Here,we report an additive strategy for finely regulating the impurities in the intermediate phase of Cs_(0.25)FA_(0.75)Pb_(0.6)Sn_(0.4)I_(3)and,thereby,obtaining high-performance solar cells.We introduced d-homoserine lactone hydrochloride(D-HLH)to form hydrogen bonds and strong Pb-O/Sn-O bonds with perovskite precursors,thereby weakening the incomplete complexation effect between polar aprotic solvents(e.g.,DMSO)and organic(FAI)or inorganic(CsI,PbI_(2),and SnI_(2))components,and balancing their nucleation processes.This treatment completely transformed mixed intermediate phases into pure preformed perovskite nuclei prior to thermal anneal-ing.Besides,this D-HLH substantially inhibited the oxidation of Sn^(2+) species.This strategy generated a record efficiency of 21.61%,with a Voc of 0.88 V for an MA-free Sn-Pb device,and an efficiency of 23.82%for its tandem device.The unencapsulated devices displayed impressive thermal stability at 85℃ for 300 h and much improved continuous operation stability at MPP for 120 h.
基金Supported by National National Science Foundation (20464002)
文摘Changes of surface shape, aggregate state, and microstructure of Apocynum fiber before and after irradia-tion were studied by XRD, IR, SEM, ESR, and solid state 13C CP/ MAS NMR. The results show that the surface shape and microstructure were not spoiled under 50 kGy gamma irradiation, while the crystallization of Apocynum fiber changed under 280 kGy . It also shows that different free radicals appear after irradiation and their concentration increases with the increase of irradiation dose.
