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DOE OSTI · 3409969

Open-air spray deposition of PCBM/BCP electron transport layer for inverted perovskite solar cells

Chen, Justin P. [Stanford University, CA (United States)]·Colburn, Thomas W. [Stanford University, CA (United States)]·Risner-Jamtgaard, Juliet [Stanford University, CA (United States)]·Vailionis, Arturas [Stanford University, CA (United States); Kaunas University of Technology (Lithuania)]·Barnum, Andrew [Stanford University, CA (United States)]·Golding, Margarita [Stanford University, CA (United States)]·Carbone, Abigail [Stanford University, CA (United States)]·Flick, Austin C. [Stanford University, CA (United States)]·Dauskardt, Reinhold H. [Stanford University, CA (United States)] (ORCID:000000033989362X)
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Abstract

A [6,6]-phenyl C61 butyric acid methyl ester (PCBM) and bathocuproine (BCP) electron transport layer (ETL) is spray deposited in open air directly on top of a perovskite at linear speeds of 9 m/min. The PCBM precursor ink contains a binary mixture of 1:1 chlorobenzene:chloroform, which optimizes spray wettability on the perovskite surface and allows quick solvent evaporation. A near-infrared heating module additionally provides a flash cure (<5 s) for the formation of smooth, large-area PCBM films (∼20 cm 2 ). A BCP solution in isopropanol is subsequently sprayed to form an ultrathin (<5 nm) film and characterized with a suite of high-resolution metrologies. The spray-deposition processing and near-infrared treatment do not damage the underlying perovskite. Inverted architecture devices containing the sprayed ETL achieve a champion efficiency of 20.3% and demonstrate stable performance without additional interlayers or surface treatments. Here, the technoeconomic cost of the open-air spray process is compared against traditional vacuum-based evaporation, resulting in a decrease in manufacturing costs by 26%.

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14 SOLAR ENERGY36 MATERIALS SCIENCEBCPPCBMelectron transport layeropen airperovskitephotovoltaicsrapid thermal processingsolar cellsspray depositionthin filmultrasonic spray

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Chen, Justin P. [Stanford University, CA (United States)], Colburn, Thomas W. [Stanford University, CA (United States)], Risner-Jamtgaard, Juliet [Stanford University, CA (United States)], Vailionis, Arturas [Stanford University, CA (United States); Kaunas University of Technology (Lithuania)], Barnum, Andrew [Stanford University, CA (United States)], Golding, Margarita [Stanford University, CA (United States)], Carbone, Abigail [Stanford University, CA (United States)], Flick, Austin C. [Stanford University, CA (United States)], Dauskardt, Reinhold H. [Stanford University, CA (United States)] (ORCID:000000033989362X). 2025-03-05. Open-air spray deposition of PCBM/BCP electron transport layer for inverted perovskite solar cells. https://doi.org/10.1016/j.matt.2025.101990

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