Tailoring carrier dynamics in perovskite solar cells via precise dimension and architecture control and interfacial positioning of plasmonic nanoparticles
Tailoring carrier dynamics in perovskite solar cells via precise dimension and architecture control and interfacial positioning of plasmonic nanoparticles
复制标题
通过精确的尺寸和结构控制以及等离子体纳米颗粒的界面定位来定制钙钛矿太阳能电池中的载流子动力学
DOI：
10.1039/c9ee03937f
复制
发表时间：
2020-06-01
影响因子：
32.5
通讯作者：
Lin, Zhiqun
中科院分区：
文献类型：
--
作者：
Cui, Xun;Chen, Yihuang;Lin, Zhiqun
将等离子体纳米粒子（NPs）放置在半导体纳米结构附近，通过局部表面等离子体共振（LSPR）诱导的光吸收增强和/或促进载流子输运，可以有效地调谐半导体的光电特性。本文首次报道了钙钛矿太阳能电池（PSCs）的载流子动力学，通过将单分散等离子体/介电芯/壳NPs与系统变化的介电壳厚度和固定的等离子体核直径夹在电子传输层（ETL）内。具体来说，通过利用星形嵌段共聚物纳米反应器策略，首先制作了一组具有精确控制尺寸（即固定的Au核直径和可调的SiO2壳厚度）和结构（普通Au核ps和等离子体/介电Au/SiO2核/壳NPs）的Au核ps。随后，这些单分散的NPs被夹在两个连续的TiO2 etl之间。有趣的是，SiO2存在一个临界介电层厚度，在此厚度以下，来自Au核心的热电子很容易注入到TiO2中（即热电子转移（HET））；这促进了TiO2 ETL中的局部电子迁移，从而改善了电荷输运和增加了短路电流密度（Jsc）。同样值得注意的是，HET效应提高了TiO2的费米能级，导致内置电位和开路电压（Voc）增强。综上所述，采用三明治状TiO2/Au NPs/TiO2 ETL构建的psc具有显著增强的Jsc和Voc，在平面和介观结构psc中分别获得18.81%和19.42%的冠军pce。因此，合理设计的单分散等离子体NPs在ETL中的合理定位可以有效地定制载流子动力学，从而为开发高性能psc提供了独特的平台。
Placing plasmonic nanoparticles (NPs) in close proximity to semiconductor nanostructures renders effective tuning of the optoelectronic properties of semiconductors through the localized surface plasmon resonance (LSPR)-induced enhancement of light absorption and/or promotion of carrier transport. Herein, we report on, for the first time, the scrutiny of carrier dynamics of perovskite solar cells (PSCs) via sandwiching monodisperse plasmonic/dielectric core/shell NPs with systematically varied dielectric shell thickness yet fixed plasmonic core diameter within an electron transport layer (ETL). Specifically, a set of Au NPs with precisely controlled dimensions (i.e., fixed Au core diameter and tunable SiO2 shell thickness) and architectures (plain Au NPs and plasmonic/dielectric Au/SiO2 core/shell NPs) are first crafted by capitalizing on the star-like block copolymer nanoreactor strategy. Subsequently, these monodisperse NPs are sandwiched between the two consecutive TiO2 ETLs. Intriguingly, there exists a critical dielectric SiO2 shell thickness, below which hot electrons from the Au core are readily injected to TiO2 (i.e., hot electron transfer (HET)); this promotes local electron mobility in the TiO2 ETL, leading to improved charge transport and increased short-circuit current density (Jsc). It is also notable that the HET effect moves up the Fermi level of TiO2, resulting in an enhanced built-in potential and open-circuit voltage (Voc). Taken together, the PSCs constructed by employing a sandwich-like TiO2/Au NPs/TiO2 ETL exhibit both greatly enhanced Jsc and Voc, delivering champion PCEs of 18.81% and 19.42% in planar and mesostructured PSCs, respectively. As such, the judicious positioning of rationally designed monodisperse plasmonic NPs in the ETL affords effective tailoring of carrier dynamics, thereby providing a unique platform for developing high-performance PSCs.