Halide perovskites with low-dimensionalities(2D or quasi-2D)have demonstrated outstanding stabilities compared to their 3D counterparts.Nevertheless,poor charge-transporting abilities of organic components in 2D perov...Halide perovskites with low-dimensionalities(2D or quasi-2D)have demonstrated outstanding stabilities compared to their 3D counterparts.Nevertheless,poor charge-transporting abilities of organic components in 2D perovskites lead to relatively low power conversion efficiency(PCE)and thus limit their applications in photovoltaics.Here,we report a novel hole-transporting low-dimensional(HT2D)perovskite,which can form a hole-transporting channel on the top surface of 3D perovskite due to self-assembly effects of metal halide frameworks.This HT2D perovskite can significantly reduce interface trap densities and enhance hole-extracting abilities of a heterojunction region between the 3D perovskite and hole-transporting layer.Furthermore,the posttreatment by HT2D can also reduce the crystal defects of perovskite and improve film morphology.As a result,perovskite solar cells(PSCs)can effectively suppress nonradiative recombination,leading to an increasement on photovoltage to>1.20 V and thus achieving>20%power conversion efficiency and>500 h continuous illumination stability.This work provides a pathway to overcome charge-transporting limitations in low-dimensional perovskites and delivers significant enhancements on performance of PSCs.展开更多
基金supported financially by the National Key Research and Development Program of China(2017YFE0131900)National Natural Science Foundation of China(91833306,91733302,62075094,52003118)+4 种基金Ningbo Natural Science Foundation(202003N4004)the Joint Research Funds of Department of Science&Technology of Shaanxi Province and Northwestern Polytechnical University(2020GXLH-Z-014)the Recruitment Program of Global Expertsthe Innovation and Entrepreneurship Program of Jiangsu Provinceand the Six Talent Peak Project of Jiangsu Province(XNY-026)。
文摘Halide perovskites with low-dimensionalities(2D or quasi-2D)have demonstrated outstanding stabilities compared to their 3D counterparts.Nevertheless,poor charge-transporting abilities of organic components in 2D perovskites lead to relatively low power conversion efficiency(PCE)and thus limit their applications in photovoltaics.Here,we report a novel hole-transporting low-dimensional(HT2D)perovskite,which can form a hole-transporting channel on the top surface of 3D perovskite due to self-assembly effects of metal halide frameworks.This HT2D perovskite can significantly reduce interface trap densities and enhance hole-extracting abilities of a heterojunction region between the 3D perovskite and hole-transporting layer.Furthermore,the posttreatment by HT2D can also reduce the crystal defects of perovskite and improve film morphology.As a result,perovskite solar cells(PSCs)can effectively suppress nonradiative recombination,leading to an increasement on photovoltage to>1.20 V and thus achieving>20%power conversion efficiency and>500 h continuous illumination stability.This work provides a pathway to overcome charge-transporting limitations in low-dimensional perovskites and delivers significant enhancements on performance of PSCs.