Role of Electron- and Hole-Collecting Buffer Layers on the Stability of Inverted Polymer: Fullerene Photovoltaic Devices

Author

Voroshazi, Eszter ; Cardinaletti, Ilaria ; Uytterhoeven, Griet ; Shan Li ; Empl, Max ; Aernouts, Tom ; Rand, Barry P.

Author_Institution

imec, Leuven, Belgium

Volume

4

Issue

1

fYear

2014

fDate

Jan. 2014

Firstpage

265

Lastpage

270

Abstract

Systematic device performance and air stability comparison of inverted architecture polythiophene:fullerene photovoltaic cells with eight different electron-collecting layers (ECLs) and two hole-collecting layers are presented in this study. Regardless of the ECL, we achieved an efficiency of over 3.5% and lifetime of over 1000 h. These results indicate the relative interchangeability of various solution-processed ECLs. Long-term (>5000 h) air exposure revealed a secondary failure mechanism of inverted cells, which is assigned to hindered exciton harvesting. Notably, devices with a polymeric hole-collecting layer and Ag/Al electrode exhibited the longest lifetime (defined as 80% of the initial performance) of 4000 h, compared with 3000 h for MoO 3/Ag/Al.

Keywords

buffer layers; excitons; polymers; solar cells; Ag-Al electrode; air stability; electron-collecting buffer layer; exciton harvesting; hole-collecting buffer layer; inverted architecture polythiophene-fullerene photovoltaic cells; inverted cells; inverted polymer-fullerene photovoltaic device stability; long-term air exposure; polymeric hole-collecting layer; relative interchangeability; secondary failure mechanism; solution-processed electron-collecting layers; systematic device performance; time 4000 h; Aging; Degradation; Humidity; Metals; Performance evaluation; Photovoltaic cells; Polymers; Degradation; interface phenomena; organic semiconductors; oxygen; solar cells;

fLanguage

English

Journal_Title

Photovoltaics, IEEE Journal of

Publisher

ieee

ISSN

2156-3381

Type

jour

DOI

10.1109/JPHOTOV.2013.2287913

Filename

6664999