Effect of methylamine vapor exposure and ambient ageing on Cs(x)MA(1-x)PbI(3-x)Br(x) perovskites for improved carrier collection

Singh, Akash and Chouhan, Arun Singh and Avasthi, Sushobhan (2019) Effect of methylamine vapor exposure and ambient ageing on Cs(x)MA(1-x)PbI(3-x)Br(x) perovskites for improved carrier collection. In: MATERIALS RESEARCH EXPRESS, 6 (8).

PDF Mat_Res_Exp_6_8_2019.pdf - Published Version Restricted to Registered users only Download (1MB) | Request a copy

Abstract

Caesium-methylammonium lead iodide-bromide perovskites (Cs(x)MA(1-x)PbI(3-x)Br(x)) is interesting for stable and high-voltage tandem solar cells. Here, we report a systematic material and device study of Cs(x)MA(1-x)PbI(3-x)Br(x) (x = 0, 5, 10 and 15%) perovskite films. Cs-Br incorporation reduces carrier lifetime of as-deposited films, from 21.5 mu s for x = 0% to 5.8 mu s for x = 15%. Unlike pure MA films, Cs-Br incorporated films were not only more resilient to degradation, their carrier lifetime increased by 50%-300% when exposed to ambient due to the humidity-assisted healing. The morphology of asdeposited films was poor. Methylamine vapor exposure (MVE) was used to improve the morphology and crystallinity, which further improved carrier lifetime up to 50 ps. Devices with efficiency >17% were fabricated on MVE treated Cs(0.10)MA(0.90)PbI(2.90)Br(0.10) films. The short circuit current density was further increased by fabricating devices on `aged' films which have higher lifetime due to humidity healing. Best Cs(0.10)MA(0.90)PbI(2.90)Br(0.10) devices show good ambient stability with V-OC and FF unchanged even after 5 days of ambient exposure.

Item Type:	Journal Article
Publication:	MATERIALS RESEARCH EXPRESS
Publisher:	IOP PUBLISHING LTD
Additional Information:	copyright for this article belongs to IOP PUBLISHING LTD
Keywords:	carrier collection; carrier lifetime; humidity healing; methylamine healing; mixed-cation perovskites; solar-cells
Department/Centre:	Division of Interdisciplinary Sciences > Centre for Nano Science and Engineering
Date Deposited:	23 Jul 2019 09:25
Last Modified:	23 Jul 2019 09:25
URI:	http://eprints.iisc.ac.in/id/eprint/62853

Actions (login required)

View Item