| 초록 |
SnO2 is a very promising material as electron transport layer (ETL) in perovskite solar cells (PSCs). However, efficiency of SnO2 based PSCs is still lower than that of high temperature processed TiO2 ETL. In this work, we report a new type of bilayer ETL using SnO2 sphere and Zn doped SnO2 nanorod to improve the performance of PSCs. Compared with the PSCs using a typical spherical SnO2 ETL (PCE = 20%, Voc = 1.14 V, Jsc = 22.4 and FF = 78.9% ), the performance of the bi-layer structured ETL based PSC (PCE = 21.1%, Voc = 1.16 V, Jsc = 23.3 and FF = 78.9% ) is dramatically improved. This improved performance can be attributed to the higher transmittance, effective blocking effect, and superior charge collection property of bilayer ETL. In addition, bilayer ETL based flexible PSCs show superior device performance beyond 21%, which is the highest efficiency among all flexible PSCs, demonstrating its potential for application into flexible device. |
