摘要
窄带隙锡-铅混合钙钛矿太阳电池(PSCs)的效率有望接近Shockley-Queisser极限,然而,易氧化的亚锡离子Sn^(2+)以及载流子传输层/钙钛矿未优化的界面接触会导致严重的界面电荷复合和器件性能下降,这在很大程度上阻碍了锡-铅混合钙钛矿太阳电池的实际应用,本文通过在钙钛矿中掺入少量有机膦酸咔唑分子,成功地制备了无空穴传输层锡-铅混合钙钛矿太阳电池.相对于Pb^(2+),有机磷酸咔唑分子在晶界处和晶体表面与Sn^(2+)离子有更强的化学配位作用,从而有效抑制Sn^(2+)的氧化,钝化缺陷并抑制非辐射复合。在移除空穴传输层的情况下,此类有机膦酸咔唑分子靶向修饰作用可有效增强内建电场(~100mV),优化透明导电基底与钙钛矿层的能级排列,从而加速光生电荷分离,促进界面空穴抽取和传输.最终,无空穴传输层的锡-铅混合钙钛矿太阳电池获得最高20.21%的光电转换效率,开路电压高达0.87V,同时实现了超过2400小时的长期稳定性。
Narrow-bandgap mixed Sn-Pb perovskite solar cells(PSCs)have showcased great potential to approach the Shockley-Queisser limit.Nevertheless,the practical application and long-term deployment of mixed Sn-Pb PSCs are still largely impeded by the rapid oxidation of Sn^(2+) ions and under-optimized carrier transport layer(CTL)/perovskite interfaces that would inevitably incur serious interfacial charge recombination and device performance degradation.Herein,we successfully removed the hole transport layer(HTL)by incorporating a small amount of organic phosphonic acid molecules into perovskites,which could preferably interact with Sn^(2+) ions(relative to Pb^(2+) analogues)at the grain boundaries(GBs)throughout the perovskite film thickness via coordination bonding,thus effectively retarding the oxidation of Sn^(2+),passivating the defects and suppressing the non-radiative recombination.Targeted modifi-cation effectively reinforced built-in potential by100 mV,and favorably induced energy level cascade,thus accelerating spatial charge separation and facilitating the hole extraction from perovskite layer to underlying conductive electrodes even in the absence of HTL.Consequently,enhanced power conversion efficiencies up to 20.21%have been achieved,which is the record efficiency for the HTLfree mixed Sn-Pb PSCs,accompanied by a decent photovoltage of 0.87 V and improved long-term stability over 2400 h.
作者
常雪晴
钟均星
杨果
谭颖
龚力
倪兴
纪玉金
李有勇
张国栋
郑毅帆
邵宇川
周杰
仰志斌
王连洲
吴武强
Xueqing Chang;Jun-Xing Zhong;Guo Yang;Ying Tan;Li Gong;Xing Ni;Yujin Ji;Youyong Li;Guodong Zhang;Yifan Zheng;Yuchuan Shao;Jie Zhou;Zhibin Yang;Lianzhou Wang;Wu-Qiang Wu(MOE Key Laboratory of Bioinorganic and Synthetic Chemistry,Lehn Institute of Functional Materials,School of Chemistry,Sun Yat-sen University,Guangzhou 510006,China;Instrumental Analysis Research Center,Sun Yat-sen University,Guangzhou 510275,China;Nanomaterials Centre,School of Chemical Engineering and Australian Institute for Bioengineering and Nanotechnology,The University of Queensland,Brisbane QLD 4072,Australia;Institute of Functional Nano&Soft Materials(FUNSOM),Jiangsu Key Laboratory for Carbon-Based Functional Materials&Devices,Soochow University,Suzhou 215123,China;Key Laboratory of Materials for High-Power Laser,Shanghai Institute of Optics and Fine Mechanics,Chinese Academy of Sciences,Shanghai 201800,China;School of Chemistry and Chemical Engineering,Shanghai Jiao Tong University,Shanghai 200240,China)
基金
supported by the National Natural Science Foundation of China(22005355)
the Guangdong Basic and Applied Basic Research Foundation(2022A1515010282).
