Quantification of electron accumulation at grain boundaries in perovskite polycrystalline films by correlative infrared-spectroscopic nanoimaging and Kelvin probe force microscopy.
Quantification of electron accumulation at grain boundaries in perovskite polycrystalline films by correlative infrared-spectroscopic nanoimaging and Kelvin probe force microscopy.
复制标题
通过相关红外光谱纳米成像和开尔文探针力显微镜定量钙钛矿多晶薄膜晶界处的电子积累
DOI：
10.1038/s41377-021-00524-7
复制
发表时间：
2021-04-15
期刊：
影响因子：
--
通讯作者：
Tian ZQ
中科院分区：
文献类型：
--
作者：
Qin TX;You EM;Zhang MX;Zheng P;Huang XF;Ding SY;Mao BW;Tian ZQ
有机-无机卤化物钙钛矿是一种新兴的光伏应用材料，具有超过25%的认证功率转换效率(PCE)。一般来说，钙钛矿材料的微观结构对PCE的性能是至关重要的。然而，普遍存在于多晶钙钛矿薄膜中的纳米晶界(GBs)的作用对太阳能电池的性能是有利的还是有害的，仍然存在争议。因此，纳米分辨的电荷载流子分布的定量来阐明基团的作用是非常必要的。在这里，我们利用相关的红外光谱纳米成像技术，利用空间分辨率为20 nm的散射型扫描近场光学显微镜和开尔文探针力显微镜来量化钙钛矿型多晶薄膜中聚集在基团处的电子密度。结果表明，在5 32 nm光照下，电子密度从6 × 10 19 cm−3增加到8 × 1019 cm−3，在10 min的光照下，电子积累增强，电子密度从暗时的6 ×10 19 cm−3增加到8 × 1019。结果表明，在光照条件下，GBS的电子积累增强，向下弯曲，有利于电子-空穴的分离，有利于太阳电池的性能。通过散射型扫描近场光学显微镜和开尔文探针力显微镜的相关红外光谱纳米成像定量地揭示了钙钛矿型多晶薄膜中GBs处积累的电子。
Organic–inorganic halide perovskites are emerging materials for photovoltaic applications with certified power conversion efficiencies (PCEs) over 25%. Generally, the microstructures of the perovskite materials are critical to the performances of PCEs. However, the role of the nanometer-sized grain boundaries (GBs) that universally existing in polycrystalline perovskite films could be benign or detrimental to solar cell performance, still remains controversial. Thus, nanometer-resolved quantification of charge carrier distribution to elucidate the role of GBs is highly desirable. Here, we employ correlative infrared-spectroscopic nanoimaging by the scattering-type scanning near-field optical microscopy with 20 nm spatial resolution and Kelvin probe force microscopy to quantify the density of electrons accumulated at the GBs in perovskite polycrystalline thin films. It is found that the electron accumulations are enhanced at the GBs and the electron density is increased from 6 × 1019 cm−3 in the dark to 8 × 1019 cm−3 under 10 min illumination with 532 nm light. Our results reveal that the electron accumulations are enhanced at the GBs especially under light illumination, featuring downward band bending toward the GBs, which would assist in electron-hole separation and thus be benign to the solar cell performance. Correlative infrared-spectroscopic nanoimaging by the scattering-type scanning near-field optical microscopy and Kelvin probe force microscopy quantitatively reveal the accumulated electrons at GBs in perovskite polycrystalline thin films.
登录
查看更多内容
影响因子：
7
作者：
Jung, Lena;Pries, Julian;Taubner, Thomas
通讯作者：
Taubner, Thomas
影响因子：
15
作者：
Long, Run;Liu, Jin;Prezhdo, Oleg V.
通讯作者：
Prezhdo, Oleg V.
影响因子：
17.1
作者：
Huck, Christian;Neubrech, Frank;Pucci, Annemarie
通讯作者：
Pucci, Annemarie
影响因子：
19
作者：
Lewin, Martin;Baeumer, Christoph;Taubner, Thomas
通讯作者：
Taubner, Thomas
影响因子：
15
作者：
Kojima, Akihiro;Teshima, Kenjiro;Miyasaka, Tsutomu
通讯作者：
Miyasaka, Tsutomu