Energy Level Tuning of PEDOT:PSS for High Performance Tin‐Lead Mixed Perovskite Solar Cells. Issue 2 (26th November 2018)

• Record Type: Journal Article
• Authors: Tang, Haoying; Shang, Yuequn; Zhou, Wenjia; Peng, Zijian; Ning, Zhijun
• Is Part Of: Solar RRL. Volume 3:Issue 2(2019)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2018-11-26
• Subjects: energy level tuning -- tin‐lead mixed -- perovskite solar cell -- photovoltaic devices; Solar energy -- Periodicals; Photovoltaic power generation -- Periodicals; Solar energy -- Research -- Periodicals; Photovoltaic power generation -- Research -- Periodicals; Periodicals; 333.7923
• DOI: 10.1002/solr.201800256
• Languages: English
• ISSNs: 2367-198X

Abstract

Abstract : Small bandgap Sn‐Pb mixed perovskite is generally regarded as the most promising structure to further enhance the power conversion efficiency of perovskite solar cells. However, the open circuit voltages ( V OC s) are usually lower than expected. In this work, by doping the generally used hole transporting layer (HTL) poly(3, 4‐ethylenedioxythiophene)‐poly(styrenesulfonate) (PEDOT:PSS) with a perfluorinated ionomer (PFI), we can tune the work function of it from −5.02 to −5.19 eV. This reduces the energy level mismatch between the FA0.6 MA0.4 Sn0.6 Pb0.4 I3 (FAMA) absorber and HTL, giving rise to enhanced built‐in voltage and better carrier extraction. The V OC improves to over 50 mV, up to 0.783 V, resulting in an improved champion power conversion efficiency (PCE) of 15.85%. Moreover, the devices based on modified HTLs show improved stability at maximum power point. These results demonstrate that energy level tuning of the HTL is a promising strategy for the improvement of the PCEs of Sn‐Pb mixed inverted PSCs, and the addition of PFI is an effective method to tune the work function of PEDOT:PSS. Abstract : The energy level mismatch between a FA0.6MA0.4 Sn0.6Pb0.4I3 absorber and PEDOT:PSS based hole transporting layer are reduced and an improved VOC over 50 mV and hence power conversion efficiencies of up to 15.85% are achieved.