Imbalanced charge-carrier extraction remains an issue aggravating interfacial charge accumulation and recombination.More hopping transport channels could accelerate the extraction of charge.Here,we demonstrated an eff...Imbalanced charge-carrier extraction remains an issue aggravating interfacial charge accumulation and recombination.More hopping transport channels could accelerate the extraction of charge.Here,we demonstrated an effective“bridging interface”strategy between the perovskite/2,2′,7,7′-tetrakis(N,N-di-pmethoxyphenylamine)-9,9′-spirobifluorene(spiro-OMeTAD)that modulates interfacial charge transfer and improves hole mobility using radical-containing donor-acceptor nanographenes(D-A NGs)possessing electron-deficient perchlorinated NGs and electron-rich aniline derivatives.The fully delocalized backbone of nanographene formed a conjugated bridge for intermolecular charge transfer and generated stable radical cations,verified by electron spin resonance.Lamellar andπ-πstacking orientation of D-A NGs also provided advantageous hopping transport channels.Besides favorable charge transfer within D-A NGs,systematic explorations indicated a strong interface coupling and noticeable charge transfer across the D-A NGs and perovskite interface,where electrons would flow from D-A NGs to perovskite,and holes would flow from perovskite to D-A NGs.Moreover,the hole mobility of spiro-OMeTAD was also enhanced because the D-A NGs would diffuse into the spiro-OMeTAD layer.As a result,planar n-i-p perovskite solar cellsmodified byD-ANG-OMe/D-ANG-tBudeliveredchampion power conversion efficiencies(PCEs)of 23.25%and 23.51%,respectively.展开更多
The recent dramatic rise in power conversion efficiencies（PCE）of perovskite solar cells has triggered intense research worldwide.However,their practical development is hampered by poor stability and low PCE values w...The recent dramatic rise in power conversion efficiencies（PCE）of perovskite solar cells has triggered intense research worldwide.However,their practical development is hampered by poor stability and low PCE values with large areas devices.Here,we developed a gas-pumping method to avoid pinholes and eliminate local structural defects over large areas of perovskite film,even for 5 × 5 cm^2 modules,the PCE reached 10.6%and no significant degradation was found after 140 days of outdoor testing.Our approach enables the realization of high performance large-area PSCs for practical application.展开更多
基金the financial support from the National Natural Science Foundation of China(grant nos.21975260 and 22175180)the National Natural Science Foundation of China-National Research Council of Italy(NSFC-CNR)Exchange Program of NSFC(grant no.22011530391)The GIWAXS measurements were performed at SPring-8 with the approval of the Japan Synchrotron Radiation Research Institute(grant nos.2022A1654,2022A1777,and 2022A1822).
文摘Imbalanced charge-carrier extraction remains an issue aggravating interfacial charge accumulation and recombination.More hopping transport channels could accelerate the extraction of charge.Here,we demonstrated an effective“bridging interface”strategy between the perovskite/2,2′,7,7′-tetrakis(N,N-di-pmethoxyphenylamine)-9,9′-spirobifluorene(spiro-OMeTAD)that modulates interfacial charge transfer and improves hole mobility using radical-containing donor-acceptor nanographenes(D-A NGs)possessing electron-deficient perchlorinated NGs and electron-rich aniline derivatives.The fully delocalized backbone of nanographene formed a conjugated bridge for intermolecular charge transfer and generated stable radical cations,verified by electron spin resonance.Lamellar andπ-πstacking orientation of D-A NGs also provided advantageous hopping transport channels.Besides favorable charge transfer within D-A NGs,systematic explorations indicated a strong interface coupling and noticeable charge transfer across the D-A NGs and perovskite interface,where electrons would flow from D-A NGs to perovskite,and holes would flow from perovskite to D-A NGs.Moreover,the hole mobility of spiro-OMeTAD was also enhanced because the D-A NGs would diffuse into the spiro-OMeTAD layer.As a result,planar n-i-p perovskite solar cellsmodified byD-ANG-OMe/D-ANG-tBudeliveredchampion power conversion efficiencies(PCEs)of 23.25%and 23.51%,respectively.
文摘The recent dramatic rise in power conversion efficiencies（PCE）of perovskite solar cells has triggered intense research worldwide.However,their practical development is hampered by poor stability and low PCE values with large areas devices.Here,we developed a gas-pumping method to avoid pinholes and eliminate local structural defects over large areas of perovskite film,even for 5 × 5 cm^2 modules,the PCE reached 10.6%and no significant degradation was found after 140 days of outdoor testing.Our approach enables the realization of high performance large-area PSCs for practical application.
