Suppressing the Surface Recombination and Tuning the Open-Circuit Voltage of Polymer/Fullerene Solar Cells by Implementing an Aggregative Ternary Compound

Galli D, Gasparini N, Forster M, Eckert A, Widling C, Killian M, Avgeropoulos A, Gregoriou VG, Scherf U, Chochos CL, Brabec C, Ameri T (2018)

Publication Language: English

Publication Status: Published

Publication Type: Journal article, Original article

Publication year: 2018

Journal

Publisher: American Chemical Society

Book Volume: 10

Pages Range: 28803-28811

Journal Issue: 34

DOI: 10.1021/acsami.8b09174

Abstract

In this work, we present a novel small molecule based on dithienylthienothiadiazole units (named SM1) acting as an efficient component in ternary blend organic solar cells to modify the hole extraction at the interface. Our findings show that the SM1 suppresses the surface recombination and enhances the open-circuit voltage (V_oc). By introducing SM1 in a host system composed of poly(3-hexylthiophene) (P3HT) and [6,6]-phenyl-C₆₁-butyric acid methyl ester (PCBM), we obtained V_oc values of up to 0.75 V and fill factors larger than 70% for the ternary blends. As a consequence, the power conversion efficiency is improved by about 30% compared to P3HT:PCBM binary devices. Interestingly, external quantum efficiency and absorption spectra in the near-infrared region do not show any contribution of SM1 in dried films. Instead, the addition of the small molecule improves the V_oc by reducing the surface recombination losses. To shed light on the recombination processes, we carried out Fourier-transform photocurrent spectroscopy and impedance spectroscopy measurements. This work shows that the ternary concept can also have functionalities other than photosensitization and can even act as a morphology-directing agent or an interface modifier.

Authors with CRIS profile

Involved external institutions

Bergische Universität Wuppertal Germany (DE) Advent Technologies SA Greece (GR) University of Ioannina / Πανεπιστήμιο Ιωαννίνων Greece (GR)

How to cite

APA:

Galli, D., Gasparini, N., Forster, M., Eckert, A., Widling, C., Killian, M.,... Ameri, T. (2018). Suppressing the Surface Recombination and Tuning the Open-Circuit Voltage of Polymer/Fullerene Solar Cells by Implementing an Aggregative Ternary Compound. ACS Applied Materials and Interfaces, 10(34), 28803-28811. https://dx.doi.org/10.1021/acsami.8b09174

MLA:

Galli, Diana, et al. "Suppressing the Surface Recombination and Tuning the Open-Circuit Voltage of Polymer/Fullerene Solar Cells by Implementing an Aggregative Ternary Compound." ACS Applied Materials and Interfaces 10.34 (2018): 28803-28811.

BibTeX: Download