0
Technical Brief

# Effect of 1,8-Diiodooctane on the Performance of P3HT:PCBM Solar Cells

[+] Author and Article Information
M. Nasiri

Institute of Polymeric Materials,
Sahand University of Technology,
Tabriz 5331711111, Iran
Faculty of Polymer Engineering,
Sahand University of Technology,
Tabriz 5331711111, Iran

F. Abbasi

Institute of Polymeric Materials,
Sahand University of Technology,
Tabriz 5331711111, Iran
Faculty of Polymer Engineering,
Sahand University of Technology,
Tabriz 5331711111, Iran
e-mail: f.abbasi@sut.ac.ir

1Corresponding author.

Contributed by the Solar Energy Division of ASME for publication in the JOURNAL OF SOLAR ENERGY ENGINEERING: INCLUDING WIND ENERGY AND BUILDING ENERGY CONSERVATION. Manuscript received October 15, 2014; final manuscript received February 4, 2015; published online March 12, 2015. Editor: Robert F. Boehm.

J. Sol. Energy Eng 137(3), 034506 (Jun 01, 2015) (5 pages) Paper No: SOL-14-1305; doi: 10.1115/1.4029863 History: Received October 15, 2014; Revised February 04, 2015; Online March 12, 2015

## Abstract

Effect of 1,8-diiodooctane on the performance of poly(3-hexylthiophene) (P3HT):[6,6]-phenyl-C61-butyric acid methyl ester (PCBM) solar cells with glass/indium tin oxide (ITO)/poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS)/P3HT: PCBM/Ca/Al structure was studied. The morphology and thickness of the active layer were investigated using atomic force microscopy (AFM). The UV-visible spectroscopy and X-ray diffraction (XRD) analysis were used to study the absorption behavior (of the solutions and coated layers) and crystallinity of the active layer, respectively. The results show that the existence of 1,8-diiodooctane reduced the open circuit voltage from 0.81 to 0.52 V and increased the short circuit current by about three folds; the fill factor (FF) and power conversion efficiency were increased from 36.0 to 54.1% and 0.47% to 1.54%, respectively. These changes can be attributed to the enhanced crystallinity of P3HT or the doping effect of 1,8-diiodooctane on P3HT chains. UV-visible analysis demonstrated that the addition of 1,8-diiodooctane to the solution did not change the absorption onset, whereas in the coated layers, the maximum absorption peak shifted to higher wavelengths. The XRD analyses demonstrated the enhancement of crystallinity of P3HT upon the introduction of 1,8-diiodooctane.

<>

## Figures

Fig. 1

I–V characteristics of the samples with 1:2 P3HT:PCBM ratio, 10 mg/ml P3HT concentration: with and without 1% 1,8-diiodooctane

Fig. 2

Dark I–V characteristics of the samples with 1:2 P3HT:PCBM ratio, 10 mg/ml P3HT concentration; with and without 1% 1,8-diiodooctane in a semilog scale

Fig. 3

I–V characteristics of the sample without 1,8-diiodooctane. Thermal annealing, after encapsulation with epoxy resin, was carried out at 120 °C and different time periods.

Fig. 4

XRD spectra of the samples with 1:2 P3HT:PCBM ratio, 10 mg/ml P3HT concentration; with and without 1% diiodooctane

Fig. 5

UV-visible spectra of the samples with 1:2 P3HT:PCBM ratio, 10 mg/ml P3HT concentration. The spectrum of the sample without diiodooctane was taken from solution. The spectra of the samples with 1% diiodooctane were taken from solution and after coating on quartz.

Fig. 6

AFM images of the sample with 1:2 P3HT:PCBM ratio, 10 mg/ml P3HT concentration, and without diiodooctane; topography image (left) and phase image (right)

Fig. 7

AFM images of the sample with 1:2 P3HT:PCBM ratio, 10 mg/ml P3HT concentration, and with 1% diiodooctane; topography image (left) and phase image (right)

## Discussions

Some tools below are only available to our subscribers or users with an online account.

### Related Content

Customize your page view by dragging and repositioning the boxes below.

Related Journal Articles
Related Proceedings Articles
Related eBook Content
Topic Collections