A multifaceted ferrocene interlayer for highly stable and efficient lithium doped spiro‐OMeTAD‐based perovskite solar cells

Webb, T. et al. (2022) A multifaceted ferrocene interlayer for highly stable and efficient lithium doped spiro‐OMeTAD‐based perovskite solar cells. Advanced Energy Materials, 12(26), 2200666. (doi: 10.1002/aenm.202200666)

Abstract

Over the last decade, 2,2″,7,7″-Tetrakis[N,N-di(4-methoxyphenyl)amino]-9,9′-spirobifluorene (spiro-OMeTAD) has remained the hole transporting layer (HTL) of choice for producing high efficiency perovskite solar cells (PSCs). However, PSCs incorporating spiro-OMeTAD suffer significantly from dopant induced instability and non-ideal band alignments. Herein, a new approach is presented for tackling these issues using the functionality of organometallocenes to bind to Li+ dopant ions, rendering them immobile and reducing their impact on the degradation of PSCs. Consequently, significant improvements are observed in device stability under elevated temperature and humidity, conditions in which ion migration occurs most readily. Remarkably, PSCs prepared with ferrocene retain 70% of the initial power conversion efficiency (PCE) after a period of 1250 h as compared to only 8% in the control. Synergistically, it is also identified that ferrocene improves the hole extraction yield at the HTL interface and reduces interfacial recombination enabling PCEs to reach 23.45%. This work offers a pathway for producing highly efficient spiro-OMeTAD devices with conventional dopants via addressing the key challenge of dopant induced instability in leading PSCs.

• Item Type: Articles
• Additional Information: T.W. gratefully thanks the University of Surrey doctoral college for their support through the DCSA3 scheme. X.L. acknowledges the stipend support from Zhengzhou University and University of Surrey studentship. S.J received funding from the European Union's Horizon 2020 Research and Innovation Program under Grant Agreement No. 953187 (MUSICODE). K.D.G.I.J. gratefully acknowledges financial support from the Equality Foundation of Hong Kong. W.H.K.P. acknowledges support from the University of Surrey Doctoral College Studentship scheme. S.K, D.S., and M.A. acknowledge the financial support of this work by the Engineering and Physical Sciences Research Council (EPSRC) grant “3D OrbiSIMS: Label free chemical imaging of materials, cells and tissue” (Grant Code EP/P029868/1). T.J.M. thanks the Royal Commission for the Exhibition of 1851 for their financial support through a Research Fellowship. S.A.H. acknowledges financial support from EPSRC (Grant Number EP/R020574/1) and the UKRI Global Challenge Research Fund project SUNRISE (Grant Number EP/P032591/1). S.J.S. gratefully acknowledges the support of EPSRC (UK) under Grant Number EP/N021037/1. W.Z. acknowledges UK Engineering and Physical Sciences Research Council (EPSRC) New Investigator Award (2018; EP/R043272/1) and Newton Advanced Fellowship (192097) for financial support.
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Sweeney, Professor Stephen
• Authors: Webb, T., Liu, X., Westbrook, R. J.E., Kern, S., Sajjad, M. T., Jenatsch, S., Jayawardena, K. D. G. I., Perera, W. H. K., Marko, I. P., Sathasivam, S., Li, B., Yavari, M., Scurr, D. J., Alexander, M. R., Macdonald, T. J., Haque, S. A., Sweeney, S. J., and Zhang, W.
• College/School: College of Science and Engineering > School of Engineering > Electronics and Nanoscale Engineering
• Journal Name: Advanced Energy Materials
• Publisher: Wiley
• ISSN: 1614-6832
• ISSN (Online): 1614-6840
• Published Online: 20 May 2022
• Copyright Holders: Copyright © 2022 The Authors
• First Published: First published in Advanced Energy Materials 12(26):2200666
• Publisher Policy: Reproduced under a Creative Commons License