Document Type

Journal Article

Department/Unit

Department of Physics

Language

English

Abstract

The properties of the hole transporting layer (HTL) play an important role in determining the performance of the inverted planar perovskite solar cells (PSCs). High performing methylammonium lead iodide PSCs were demonstrated through controlled growth of the perovskite layer and suppression of charge recombination at the perovskite/electrode interfaces. In this work, the effect of sodium citrate modified poly (3,4-ethylenedioxythiophene): poly (4- styrenesulfonate) (PEDOT:PSS) HTL on the growth of the perovskite active layer, charge extraction properties and hence the performance of the PSCs was investigated. Power conversion efficiency (PCE) of >11.50% was achieved for low-processing temperature solution-processable PSCs made with a sodium citrate modified PEDOT:PSS HTL, which is >20% higher than that of a structurally identical control PSC with a pristine PEDOT:PSS HTL (9.13 %). Photoelectron spectroscopy measurements reveal that sodium citrate solution modification partially removes the PSS on surface of the PEDOT:PSS HTL, leading to almost two times increase in the ratio of PEDOT to PSS as compared to that measured for the pristine PEDOT:PSS HTL. Light intensity dependent J−V characteristics of the PSCs were carried out to analyze the performance enhancement of the PSCs. The results reveal that the sodium citrate modified PEDOT:PSS HTL benefits the efficient operation of PSCs in two ways: (1) it assists the crystal growth to increase in the perovskite domain size, and (2) it favors the charge collection in the PSCs.

Publication Date

1-2019

Source Publication Title

Journal of Materials Chemistry C

Volume

7

Issue

18

Start Page

5260

End Page

5266

Publisher

Royal Society of Chemistry

DOI

10.1039/C8TC06043F

Link to Publisher's Edition

https://doi.org/10.1039/C8TC06043F

ISSN (print)

20507526

Available for download on Saturday, February 01, 2020

Included in

Physics Commons

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