Kevin K. H. Chan, S. W. Tsang, Harrison K. H. Lee, F. So and S. K. So
In this contribution, charge transport properties of thin film polymers and their bulk heterojunction (BHJ) blends are probed by capacitance measurements. Six semiconducting polymers—P3HT, MDMO-PPV, PFB, TFB, PCDTBT, and PVK—were investigated by admittance spectroscopy, a powerful tool for the extraction of hole mobilities and transport parameters. For films of P3HT and PCDTBT, electron leakage occurs and obscures the extraction of hole transit times. To prevent this, a thin electron blocking and trapping interlayer between the BHJ and gold cathode is added.