Halide Perovskite Precursors Dope PEDOT:PSS. (29th June 2021)

• Record Type: Journal Article
• Authors: Sandrez, Simon; Molenda, Zuzanna; Guyot, Claire; Renault, Olivier; Barnes, Jean‐Paul; Hirsch, Lionel; Maindron, Tony; Wantz, Guillaume
• Is Part Of: Advanced Electronic Materials. Volume 7:Number 9(2021)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2021-06-29
• Subjects: doping -- halide perovskite -- PEDOT:PSS; Materials -- Electric properties -- Periodicals; Materials science -- Periodicals; Magnetic materials -- Periodicals; Electronic apparatus and appliances -- Periodicals; 537
• DOI: 10.1002/aelm.202100394
• Languages: English
• ISSNs: 2199-160X

Abstract

Abstract: Halide perovskite semiconductors find use in a broad range of optoelectronic applications including photovoltaic solar cells and light‐emitting diodes. In such devices the semiconductor is sandwiched in between interlayers for charge transport, extraction, or injection. When it comes to hole transport layers, the conducting polymer PEDOT:PSS has become an ubiquitous material. The halide perovskite thin film is commonly obtained by crystallization of precursors using solution processing on top of PEDOT:PSS. It is demonstrated here that such a widely spread technique is actually affecting the electrical properties of the underlying conducting polymer. The halide perovskite layer and precursors are drastically doping the PEDOT:PSS, its conductivity being increased by two orders of magnitude from 0.2 to 20 S cm −1 . The depth of penetration of halide dopants is determined to be higher than 150 nm, superior to the usual thickness of PEDOT:PSS films. This phenomenon has important impact on diode leakage currents, on emission patterns of perovskite LEDs and on overestimated photocurrent density in perovskite solar cells embedding the PEDOT:PSS interlayer. Abstract : Coating halide perovskite semiconductors on top of the PEDOT:PSS results in significant conductivity rise of the polymer. The halide precursors are responsible of such doping by diffusion down to at least 150 nm into PEDOT:PSS. Such unintentional doping is responsible for anomalous emission patterns in LED and overestimated photocurrents density in solar cells.