Issue 9, 2018

Slow surface passivation and crystal relaxation with additives to improve device performance and durability for tin-based perovskite solar cells

Abstract

We investigated the doping effect of bulky organic cations with ethylenediammonium diiodide (EDAI2) and butylammonium iodide (BAI) as additives to passivate surface defects, to control the film morphology and to improve the crystallinity for inverted planar FASnI3 perovskite solar cells. The addition of BAI altered significantly the orientation of crystal growth and improved the connectivity of the crystal grains, but the existence of pinholes in the surface of the pristine FASnI3 films was unavoidable; this effect impeded further improvement of the device performance (PCE 5.5%), which is nevertheless superior to that of a pristine FASnI3 film (PCE 4.0%). The addition of EDAI2 had the effect of curing the pinhole problem, passivating the surface defect states, preventing Sn2+/Sn4+ oxidation and inducing slow relaxation of the crystal structure. In the presence of the EDAI2 additive (1%), the FASnI3 device attained the best initial efficiency, 7.4%, and the device performance continuously increased as a function of duration of storage; the maximum PCE, 8.9%, was obtained for a device stored in a glove box for over 1400 h with only slight degradation for storage beyond 2000 h. The observed slow passivation of surface defects and relaxation of crystal strain were verified with X-ray diffraction, X-ray photoelectron spectroscopy and photoluminescence decay techniques.

Graphical abstract: Slow surface passivation and crystal relaxation with additives to improve device performance and durability for tin-based perovskite solar cells

Supplementary files

Article information

Article type
Communication
Submitted
02 Apr 2018
Accepted
19 Jun 2018
First published
19 Jun 2018

Energy Environ. Sci., 2018,11, 2353-2362

Slow surface passivation and crystal relaxation with additives to improve device performance and durability for tin-based perovskite solar cells

E. Jokar, C. Chien, A. Fathi, M. Rameez, Y. Chang and E. W. Diau, Energy Environ. Sci., 2018, 11, 2353 DOI: 10.1039/C8EE00956B

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements