Dissociative Host-Dopant Bonding Facilitates Molecular Doping in Halide Perovskites

Lanzetta, Luis; Gregori, Luca; Hernandez, Luis Huerta; Sharma, Anirudh; Kern, Stefanie; Kotowska, Anna M.; Emwas, Abdul-Hamid; Gutiérrez-Arzaluz, Luis; Scurr, David J.; Piggott, Matthew; Meggiolaro, Daniele; Haque, Md Azimul; De Angelis, Filippo; Baran, Derya

Abstract

Molecular doping is a promising strategy to fine-tune the electronic properties of halide perovskites and accelerate their implementation as next-generation optoelectronics. However, a deeper understanding of the role of host-dopant interactions in these systems is needed to fully exploit the potential of this avenue. Herein, we demonstrate a surface post-treatment strategy employing n-type molecular dopant n-DMBI-H to modulate free hole density in p-type CH3NH3Sn0.75Pb0.25I3 films. We show that the adsorption of n-DMBI-H on surface Sn atoms, followed by the dissociation of an electron-donating hydride from the dopant, facilitates charge transfer to perovskite and hole trapping at the dissociated hydride. We identify this mechanism as a key factor dictating doping compensation in perovskite, allowing carrier density control within nearly one order of magnitude via the dissociated molecular dopant located at film surfaces and grain boundaries. We then exploit n-DMBI-H in perovskite/transport layer junctions, achieving reduced carrier losses and improved contact selectivity and performance in p-i-n, Sn-rich perovskite solar cells. We expect this work to provide carrier density tuning guidelines for a broad range of tin-based perovskite applications.

Citation

Lanzetta, L., Gregori, L., Hernandez, L. H., Sharma, A., Kern, S., Kotowska, A. M., Emwas, A.-H., Gutiérrez-Arzaluz, L., Scurr, D. J., Piggott, M., Meggiolaro, D., Haque, M. A., De Angelis, F., & Baran, D. (2023). Dissociative Host-Dopant Bonding Facilitates Molecular Doping in Halide Perovskites. ACS Energy Letters, 8, 2858-2867. https://doi.org/10.1021/acsenergylett.3c00818

• Journal Article Type: Article
• Acceptance Date: May 24, 2023
• Online Publication Date: Jun 1, 2023
• Publication Date: Jul 14, 2023
• Deposit Date: Jul 7, 2023
• Publicly Available Date: Jun 2, 2024
• Journal: ACS Energy Letters
• Electronic ISSN: 2380-8195
• Publisher: American Chemical Society
• Peer Reviewed: Peer Reviewed
• Volume: 8
• Pages: 2858-2867
• DOI: https://doi.org/10.1021/acsenergylett.3c00818
• Public URL: https://nottingham-repository.worktribe.com/output/21378281
• Publisher URL: https://pubs.acs.org/doi/10.1021/acsenergylett.3c00818
• Additional Information: This document is the Accepted Manuscript version of a Published Work that appeared in final form in ACS Energy Letters. To access the final edited and published work see https://pubs.acs.org/doi/10.1021/acsenergylett.3c00818