无机CsPbX_(3)钙钛矿材料由于其优异的光电性能、较宽的可调带隙及简单的制备工艺而得到广泛关注。溶液制备无机CsPbX_(3)钙钛矿结晶速率过快,结晶质量不高,所获得的CsPbX_(3)薄膜体相和表面存在大量的缺陷,严重影响了CsPbX_(3)钙钛矿...无机CsPbX_(3)钙钛矿材料由于其优异的光电性能、较宽的可调带隙及简单的制备工艺而得到广泛关注。溶液制备无机CsPbX_(3)钙钛矿结晶速率过快,结晶质量不高,所获得的CsPbX_(3)薄膜体相和表面存在大量的缺陷,严重影响了CsPbX_(3)钙钛矿太阳电池(perovskite solar cells,PSCs)的效率和稳定性,因此需要调控CsPbX_(3)薄膜的结晶过程,钝化其缺陷,以便获得高质量的钙钛矿薄膜和高效、稳定的无机CsPbX_(3)PSCs。近年来,前驱体工程已被证明是获得高质量钙钛矿薄膜的有效策略。该文对无机CsPbX_(3)钙钛矿晶体结构、光电性能、制备方法及存在问题等方面进行概述,总结并讨论了基于前驱体工程制备高质量无机CsPbX_(3)钙钛矿薄膜的4种主要方法,包括组分优化、添加剂策略、中间相调控、异质结构筑。其中,组分优化能够有效调控结晶速率和结晶路径;添加剂策略实现对不同类型缺陷的钝化;中间相调控是获得优良的表面形貌和高结晶度钙钛矿薄膜的关键策略;异质结构筑是抑制不利非辐射复合,提高钙钛矿稳定性的有效策略。最后,对无机CsPbX_(3)PSCs研究的发展趋势进行了展望,在未来应该深入探索CsPbX_(3)钙钛矿薄膜结晶机理和缺陷钝化物理机制,以制备高质量钙钛矿薄膜,同时应致力于大面积器件和叠层电池的制备和开发,以实现更高的光电转换效率和商业化应用。展开更多
Surface and grain boundary defects in halide perovskite solar cells are highly detrimental,reducing efficiencies and stabilities.Widespread halide anion and organic cation defects usually aggravate ion diffusion and m...Surface and grain boundary defects in halide perovskite solar cells are highly detrimental,reducing efficiencies and stabilities.Widespread halide anion and organic cation defects usually aggravate ion diffusion and material degradation on the surfaces and at the grain boundaries of perovskite films.In this study,we employ an in-situ green method utilizing nontoxic cetyltrimethylammonium chloride(CTAC)and isopropanol(IPA)as anti-solvents to effectively passivate both surface and grain boundary defects in hybrid perovskites.Anion vacancies can be readily passivated by the chloride group due to its high electronegativity,and cation defects can be synchronously passivated by the more stable cetyltrimethylammonium group.The results show that the charge trap density was significantly reduced,while the carrier recombination lifetime was markedly extended.As a result,the power conversion efficiency of the cell can reach 23.4%with this in-situ green method.In addition,the device retains 85%of its original power conversion efficiency after 600 h of operation under illumination,showing that the stability of perovskite solar cells is improved with this in-situ passivation strategy.This work may provide a green and effective route to improve both the stability and efficiency of perovskite solar cells.展开更多
文摘无机CsPbX_(3)钙钛矿材料由于其优异的光电性能、较宽的可调带隙及简单的制备工艺而得到广泛关注。溶液制备无机CsPbX_(3)钙钛矿结晶速率过快,结晶质量不高,所获得的CsPbX_(3)薄膜体相和表面存在大量的缺陷,严重影响了CsPbX_(3)钙钛矿太阳电池(perovskite solar cells,PSCs)的效率和稳定性,因此需要调控CsPbX_(3)薄膜的结晶过程,钝化其缺陷,以便获得高质量的钙钛矿薄膜和高效、稳定的无机CsPbX_(3)PSCs。近年来,前驱体工程已被证明是获得高质量钙钛矿薄膜的有效策略。该文对无机CsPbX_(3)钙钛矿晶体结构、光电性能、制备方法及存在问题等方面进行概述,总结并讨论了基于前驱体工程制备高质量无机CsPbX_(3)钙钛矿薄膜的4种主要方法,包括组分优化、添加剂策略、中间相调控、异质结构筑。其中,组分优化能够有效调控结晶速率和结晶路径;添加剂策略实现对不同类型缺陷的钝化;中间相调控是获得优良的表面形貌和高结晶度钙钛矿薄膜的关键策略;异质结构筑是抑制不利非辐射复合,提高钙钛矿稳定性的有效策略。最后,对无机CsPbX_(3)PSCs研究的发展趋势进行了展望,在未来应该深入探索CsPbX_(3)钙钛矿薄膜结晶机理和缺陷钝化物理机制,以制备高质量钙钛矿薄膜,同时应致力于大面积器件和叠层电池的制备和开发,以实现更高的光电转换效率和商业化应用。
基金the National Key Research and Development Program of China(2016YFA0202400 and 2016YFA0202404)the National Natural Science Foundation of China(61904076 and U19A2089)+3 种基金the Natural Science Foundation of Guangdong Province(2020A1515010980 and 2019B1515120083)the Peacock Team Project funding from the Shenzhen Science and Technology Innovation Committee(KQTD2015033110182370)the Shenzhen Engineering R&D Center for Flexible Solar Cells Project funding from Shenzhen Development and Reform Committee(2019-126)the GuangdongHong Kong-Macao Joint Laboratory(2019B121205001)。
文摘Surface and grain boundary defects in halide perovskite solar cells are highly detrimental,reducing efficiencies and stabilities.Widespread halide anion and organic cation defects usually aggravate ion diffusion and material degradation on the surfaces and at the grain boundaries of perovskite films.In this study,we employ an in-situ green method utilizing nontoxic cetyltrimethylammonium chloride(CTAC)and isopropanol(IPA)as anti-solvents to effectively passivate both surface and grain boundary defects in hybrid perovskites.Anion vacancies can be readily passivated by the chloride group due to its high electronegativity,and cation defects can be synchronously passivated by the more stable cetyltrimethylammonium group.The results show that the charge trap density was significantly reduced,while the carrier recombination lifetime was markedly extended.As a result,the power conversion efficiency of the cell can reach 23.4%with this in-situ green method.In addition,the device retains 85%of its original power conversion efficiency after 600 h of operation under illumination,showing that the stability of perovskite solar cells is improved with this in-situ passivation strategy.This work may provide a green and effective route to improve both the stability and efficiency of perovskite solar cells.
