Pb-free Sn-based perovskite solar cells(PSCs) have recently made inspiring progress, and power conversion efficiency(PCE) of 14.8% has been achieved. However, due to the energy-level mismatch and poor interfacial cont...Pb-free Sn-based perovskite solar cells(PSCs) have recently made inspiring progress, and power conversion efficiency(PCE) of 14.8% has been achieved. However, due to the energy-level mismatch and poor interfacial contact between commonly used hole transport layer(i.e., poly(3,4-ethylenedioxythio phene):poly(styrene sulfonate), PEDOT:PSS) and FASnI_(3) film, it is still challenging to effectively extract holes at the interface. Owing to the p-type nature of Sn-based perovskites, the efficient hole extraction is of particular significance to improve the PCE of their solar cells. In this work, for the first time, the role of chiral cations, a-methylbenzylamine(S-/R-/rac-MBA), in promoting hole transportation of FASnI_(3)-based PSCs is demonstrated. The introduction of MBAs is found to form 2D/3D film with lowdimensional structures locating at PEDOT:PSS/FASnI_(3) interface, which facilitates the energy level alignment and efficient charge transfer at the interface. Importantly, chiral-induced spin selectivity(CISS)effect of R-MBA_(2)SnI_(4)induced by chiral R-MBA cation is found to further assist the specific interfacial transport of accumulated holes. As a result, R-MBA-based PSCs achieve decent PCE of 10.73% with much suppressed hysteresis and enhanced device stability. This work opens up a new strategy to efficiently promote the interfacial extraction of accumulated charges in working PSCs.展开更多
Enantioselective alternating copolymerization of carbon monoxide with ω undecylenic acid was carried out using cationic palladium catalyst modified by 1,4 3,6 dianhydro 2,5 dideoxy 2,5 bis(diphenylphosphino) L iditol...Enantioselective alternating copolymerization of carbon monoxide with ω undecylenic acid was carried out using cationic palladium catalyst modified by 1,4 3,6 dianhydro 2,5 dideoxy 2,5 bis(diphenylphosphino) L iditol (DDPPI). The chiral diphosphine was proved to be effective in the enantioselective copolymerization. The pure poly(1,4 ketone) was obtained by dissolving the copolymer containing spiroketal and 1,4 ketone units in 1,1,1,3,3,3 hexafluoro 2 propanol and reprecipitating with methanol. Optical rotation, elemental analysis, spectra of 1H, 13 C NMR and IR showed that our copolymer was an optically active, isotatic, alternating poly(1,4 ketone) structure. The copolymerization was carried out at 45 ℃ for 20 h. Molecular weight: n=1.1× 10 4 versus polystyrene, w/ n=1.84. Molar optical rotation: 20 589 =+43°(CH 3COOC 2H 5, 5.0 mg/mL). The productivity of the copolymer of ω undecylenic acid with carbon monoxide was 40.6 g copolymer/(g Pd·h).展开更多
Enantioselective alternating copolymerization of carbon monoxide with 1 heptene was carried out using palladium catalyst modified by 1,4 3,6 dianhydro 2,5 dideoxy 2,5 bis(diphenylphosphino) L iditol (DDPPI). The chira...Enantioselective alternating copolymerization of carbon monoxide with 1 heptene was carried out using palladium catalyst modified by 1,4 3,6 dianhydro 2,5 dideoxy 2,5 bis(diphenylphosphino) L iditol (DDPPI). The chiral diphosphine was proved to be effective at enantioselective copolymerization. The pure poly(1,4 ketone) was obtained by dissolving the copolymer containing spiroketal and 1,4 ketone units in 1,1,1,3,3,3 hexafluoro 2 propanol and reprecipitating with methanol. Optical rotation, elemental analysis, spectra of 1H\|NMR, 13 C NMR and IR showed that our copolymer was optically active, isotatic, alternating poly(1,4 ketone) structure. The copolymerization was carried out at 45℃ for 48?h. Molecular weight: M n=4 02×10 3, M w/ M n=1 55 (GPC measurements with polystyrene standards). Optical rotation:[ α ] 20 589 =+63° (CH 2Cl 2, 5 0?mg/mL). T m=194℃, T g=11℃.展开更多
基金financially supported by the Natural Science Foundation of China (Grants 51802253, 51972172, 61705102,61904152, and 91833304)the China Postdoctoral Science Foundation (Grant 2021M692630)+6 种基金the Natural Science Basic Research Plan in Shaanxi Province of China (2019JM-326)the Joint Research Funds of Department of Science&Technology of Shaanxi Province and Northwestern Polytechnical University (No. 2020GXLH-Z-007)the Natural Science Foundation of Jiangsu Province for Distinguished Young Scholars,China (Grant BK20200034)the Young 1000 Talents Global Recruitment Program of Chinathe Jiangsu Specially Appointed Professor programthe “Six talent peaks” Project in Jiangsu Province,Chinathe Fundamental Research Funds for the Central Universities。
文摘Pb-free Sn-based perovskite solar cells(PSCs) have recently made inspiring progress, and power conversion efficiency(PCE) of 14.8% has been achieved. However, due to the energy-level mismatch and poor interfacial contact between commonly used hole transport layer(i.e., poly(3,4-ethylenedioxythio phene):poly(styrene sulfonate), PEDOT:PSS) and FASnI_(3) film, it is still challenging to effectively extract holes at the interface. Owing to the p-type nature of Sn-based perovskites, the efficient hole extraction is of particular significance to improve the PCE of their solar cells. In this work, for the first time, the role of chiral cations, a-methylbenzylamine(S-/R-/rac-MBA), in promoting hole transportation of FASnI_(3)-based PSCs is demonstrated. The introduction of MBAs is found to form 2D/3D film with lowdimensional structures locating at PEDOT:PSS/FASnI_(3) interface, which facilitates the energy level alignment and efficient charge transfer at the interface. Importantly, chiral-induced spin selectivity(CISS)effect of R-MBA_(2)SnI_(4)induced by chiral R-MBA cation is found to further assist the specific interfacial transport of accumulated holes. As a result, R-MBA-based PSCs achieve decent PCE of 10.73% with much suppressed hysteresis and enhanced device stability. This work opens up a new strategy to efficiently promote the interfacial extraction of accumulated charges in working PSCs.
文摘Enantioselective alternating copolymerization of carbon monoxide with ω undecylenic acid was carried out using cationic palladium catalyst modified by 1,4 3,6 dianhydro 2,5 dideoxy 2,5 bis(diphenylphosphino) L iditol (DDPPI). The chiral diphosphine was proved to be effective in the enantioselective copolymerization. The pure poly(1,4 ketone) was obtained by dissolving the copolymer containing spiroketal and 1,4 ketone units in 1,1,1,3,3,3 hexafluoro 2 propanol and reprecipitating with methanol. Optical rotation, elemental analysis, spectra of 1H, 13 C NMR and IR showed that our copolymer was an optically active, isotatic, alternating poly(1,4 ketone) structure. The copolymerization was carried out at 45 ℃ for 20 h. Molecular weight: n=1.1× 10 4 versus polystyrene, w/ n=1.84. Molar optical rotation: 20 589 =+43°(CH 3COOC 2H 5, 5.0 mg/mL). The productivity of the copolymer of ω undecylenic acid with carbon monoxide was 40.6 g copolymer/(g Pd·h).
文摘Enantioselective alternating copolymerization of carbon monoxide with 1 heptene was carried out using palladium catalyst modified by 1,4 3,6 dianhydro 2,5 dideoxy 2,5 bis(diphenylphosphino) L iditol (DDPPI). The chiral diphosphine was proved to be effective at enantioselective copolymerization. The pure poly(1,4 ketone) was obtained by dissolving the copolymer containing spiroketal and 1,4 ketone units in 1,1,1,3,3,3 hexafluoro 2 propanol and reprecipitating with methanol. Optical rotation, elemental analysis, spectra of 1H\|NMR, 13 C NMR and IR showed that our copolymer was optically active, isotatic, alternating poly(1,4 ketone) structure. The copolymerization was carried out at 45℃ for 48?h. Molecular weight: M n=4 02×10 3, M w/ M n=1 55 (GPC measurements with polystyrene standards). Optical rotation:[ α ] 20 589 =+63° (CH 2Cl 2, 5 0?mg/mL). T m=194℃, T g=11℃.
