Take a sneak peek at the new NIST.gov and let us know what you think!
(Please note: some content may not be complete on the beta site.).

View the beta site
NIST logo

Publication Citation: Imaging of nanoscale charge transport in bulk heterojunction solar cells

NIST Authors in Bold

Author(s): Behrang H. Hamadani; Nadine E. Gergel-Hackett; Paul M. Haney; Nikolai B. Zhitenev;
Title: Imaging of nanoscale charge transport in bulk heterojunction solar cells
Published: June 17, 2011
Abstract: We have studied the local charge transport properties of organic bulk heterojunction solar cells based on the blends of poly(3-hexylthiophene) (P3HT) and phenyl-C61-butyric acid methyl ester (PCBM) with a photoconductive atomic force microscope (PCAFM). We explore the role of morphology on transport of photogenerated electrons or holes by careful consideration of the sample geometry and the choice of the atomic force microscope (AFM) tip. We then consider the role of the film/tip contact on the local current-voltage characteristics of these structures and present a model based on a drift and diffusion description of transport. We find that our simple 1D model can only reproduce qualitative features of the data using unphysical parameters, indicating that more sophisticated modeling is required to capture all the nonideal characteristics of the AFM transport measurements. Our results show that the PCAFM contrast can be directly related to the material nanomorphology only under a narrow and well-defined range of the measurement conditions.
Citation: Journal of Applied Physics
Volume: 109
Issue: 12
Pages: 7 pp.
Keywords: photoconductive AFM, organic photovoltaics, scanning probe microscopy, photocurrent
Research Areas: Nanoelectronics and Nanoscale Electronics, Energy, Materials Science, Physics, Solar, Characterization, Nanometrology, and Nanoscale Measurements
PDF version: PDF Document Click here to retrieve PDF version of paper (961KB)