Development of thick film P3HT:PCBM bulk heterojunction devices and their hole mobilities characterized by time-of-flight measurements

CHED 732

Ariel S. Marshall, asm04003@cub.uca.edu, Department of Chemistry, University of Central Arkansas, 201 Donaghey Ave., 303A Laney Hall, Conway, AR 72035, Philseok Kim, philseok.kim@chemistry.gatech.edu, School of Chemistry and Biochemistry, Georgia Institute of Technology, 901 Atlantic Drive, NW, Atlanta, GA 30332-0400, and Joseph W. Perry, joe.perry@gatech.edu, Center for Organic Photonics and Electronics, School of Chemistry and Biochemistry, Georgia Institute of Technology, 901 Atlantic Drive, NW, Atlanta, GA 30332-0400.
Thick-film, bulk-heterojunction devices based on regioregular poly(3-hexylthiophene) (P3HT) and [6,6]-Ph C61 butyric acid methyl ester (PCBM) with thickness up to 25 μm were prepared and their charge carrier mobility was determined. Thick films were processed using a melt-compression method that allows for control of thickness with a spacer. Time-of-flight photocurrent measurements using two ITO electrodes at room temperature with direct excitation of the bulk heterojunction material at 532 nm and with an applied field of 1.65 x 105 V/cm gave dispersive time of flight data, from which a hole mobility of 2 x 10-5 cm2/Vs was approximated. The estimated mobility is in the range for values reported for thin films of neat P3HT in the literature. This work was performed as part of the CMDITR STC REU program at Georgia Tech.
 

Undergraduate Research Poster Session: Polymer Chemistry
11:00 AM-1:00 PM, Monday, April 7, 2008 Morial Convention Center -- Hall A, Poster

Division of Chemical Education

The 235th ACS National Meeting, New Orleans, LA, April 6-10, 2008