Improving the electrical performance of inverted perovskite solar cell with LiF anode buffer layer

Abstract

Although the electrical performance of inverted PSCs is a bit lower than that of conventional PSCs at present, it has attracted increasing research attention thanks to its simple architecture for low preparation temperature and negligible hysteresis, and subsequently a high opportunity for industrial application. In general, PEDOT:PSS is employed to serve as hole transport layer (HTL) in inverted PSCs due to its high conductivity, high light transmittance, and aqueous dispersion. However, the mismatch of energy level between PEDOT:PSS and ITO is detrimental to extract the photo-induced holes, hampering further enhancement of the electrical performance of inverted PSCs. Here, a LiF anode buffer layer, whose optimization thickness is 7 nm, has been employed to modify the PEDOT:PSS HTL in inverted PSCs. Thanks to the LiF anode buffer layer, a dramatically enhancement of PCE from 16.01% of reference sample with pristine PEDOT:PSS to 18.18% of PSCs with LiF/PEDOT: PSS HTL. This enhancement is mainly ascribed to improve the charge extraction ability due to the diople effect of LiF. Therefore, this work provides a simple and effective method to increase the electrical performance of inverted PSCs. • A LiF anode buffer layer is employed to modify the PEDOT: PSS in inverted PSCs. • The PCE is a dramatically enhancement from 16.01% with pristine PEDOT:PSS to 18.18% with LiF/PEDOT:PSS. • This work provides a simple and effective method to increase the electrical performance of inverted PSCs.