Adv. Energy Mater.: Hot-Electron Injection in Sandwiched TiOx-Au-TiOx Structure for High Performance Planar Perovskite Solar Cells

Title：

Hot-Electron Injection in Sandwiched TiO_x-Au-TiO_x Structure for High Performance Planar Perovskite Solar Cells

Authors：

Zhongcheng Yuan^a, Zhongwei Wu^a, Sai Bai^b, Zhouhui Xia^a, Weidong Xu^a, Tao Song^a, Haihua Wu^a, Luhai Xu^a, Junjie Si^b, Yizheng Jin^b and Baoquan Sun^a*

Institutions：

^aInstitute of Functional Nano & Soft Materials (FUNSOM) and Jiangsu Key Laboratory for Carbon-Based Functional Materials &Devices, Soochow University, Suzhou, Jiangsu 215123, PR China

^bState Key Laboratory of Silicon Materials, Department of Materials Science and Engineering, Zhejiang University, Hangzhou 310027, China

Abstract：

Large amount of trap states in low temperature processed TiO_x film hindered the charge transport in perovskite solar cells. Here, gold nanoparticles (Au NPs) were incorporated into a sandwiched structure of TiO_x/Au NPs/ TiO_x to improve the charge transport properties of low temperature (150 oC) processed electron conductor layers through plasmonic-mediated hot carrier injection at metal-semiconductor Schottky junction. And based on this structure, a remarkable device performance of 16.2 % was achieved in planar perovskite device geometry. A detailed investigation on the hot-electron generation and injection process of TiO_x /Au NPs/ TiO_x composites was demonstrated to explain the origin of device improvement. Further investigation revealed that hot electrons could be injected from Au NPs to TiO_x at theplasmonic wavelength (500-600 nm) of Au NPs, resulting in increased film conductivity and surface potential of the TiOx film. The sandwitched structure of TiO_x/Au NPs/TiO_x is a key to achieve enhanced device performance to aovid any direct contact between Au NPs and perovskite, which is quite different from conjugated polymer/fullerene derivative solar cells. Our present work provides an alternative design of novel charge extracting layer toward low temperature processed highly efficiencient perovskite solar cells.

IF：

14.385

Link：

http://onlinelibrary.wiley.com/doi/10.1002/aenm.201500038/epdf

Editor: Danting Xiang