Temperature and electric field dependent hole mobility in a polyfluorene copolymer

Transport of holes in thin films of a low-bandgap alternating polyfluorene copolymer, APFO-Green5, was investigated by means of admittance spectroscopy as a function of field and temperature. The values of hole mobility were evaluated from the position of the maxima in the plots of the negative differential susceptance as a function of frequency. Hole mobility was found to be strongly field- and temperature-dependent. The charge transport parameters were extracted by analyzing the mobility data by the uncorrelated and the correlated Gaussian Disorder Models.