Critical Role of Interface and Crystallinity on the Performance and Photostability of Perovskite Solar Cell on Nickel Oxide

Wanyi Nie; Hsinhan Tsai; Jean-Christophe Blancon; Fangze Liu; Costas C Stoumpos; Boubacar Traore; Mikael Kepenekian; Olivier Durand; Claudine Katan; Sergei Tretiak; Jared Crochet; Pulickel M Ajayan; MercouriG Kanatzidis; Jacky Even; Aditya D Mohite

doi:10.1002/adma.201703879

Critical Role of Interface and Crystallinity on the Performance and Photostability of Perovskite Solar Cell on Nickel Oxide

Adv Mater. 2018 Feb;30(5). doi: 10.1002/adma.201703879. Epub 2017 Dec 11.

Authors

Affiliations

¹ Materials Physics and Application, Los Alamos National Laboratory, Los Alamos, NM, 87545, USA.
² Materials Science and Nano-engineering, Rice University, Houston, TX, 77005, USA.
³ Department of Chemistry, Department of Materials Science and Engineering, Northwestern University, Evanston, IL, 60208, USA.
⁴ Institut des Sciences Chimiques de Rennes, ISCR UMR 6226, CNRS, Université de Rennes 1, Rennes, 35042, France.
⁵ Fonctions Optiques pour les Technologies de l'Information, FOTON UMR 6082, CNRS, INSA de Rennes, Rennes, 35708, France.
⁶ Theoretical Chemistry and Molecular Physics Division, Los Alamos National Laboratory, Los Alamos, NM, 87545, USA.
⁷ Physical Chemistry and Applied Spectroscopy Division, Los Alamos National Laboratory, Los Alamos, NM, 87545, USA.

PMID: 29226392
DOI: 10.1002/adma.201703879

Abstract

Hybrid perovskites are on a trajectory toward realizing the most efficient single-junction, solution-processed photovoltaic devices. However, a critical issue is the limited understanding of the correlation between the degree of crystallinity and the emergent perovskite/hole (or electron) transport layer on device performance and photostability. Here, the controlled growth of hybrid perovskites on nickel oxide (NiO) is shown, resulting in the formation of thin films with enhanced crystallinity with characteristic peak width and splitting reminiscent of the tetragonal phase in single crystals. Photophysical and interface sensitive measurements reveal a reduced trap density at the perovskite/NiO interface in comparison with perovskites grown on poly(3,4-ethylene dioxy thiophene) polystyrene sulfonate. Photovoltaic cells exhibit a high open circuit voltage (1.12 V), indicating a near-ideal energy band alignment. Moreover, photostability of photovoltaic devices up to 10-Suns is observed, which is a direct result of the superior crystallinity of perovskite thin films on NiO. These results elucidate the critical role of the quality of the perovskite/hole transport layer interface in rendering high-performance and photostable optoelectronic devices.

Keywords: LiNiO; crystallinity; perovskite solar cells; photostability.