Authors: Nopporn Rujisamphan Thidarat Supasai Thomas Dittrich
Publish Date: 2016/01/22
Volume: 122, Issue: 2, Pages: 77-
Abstract
Results of a temperature dependence study of photoinduced charge separation across P3HT nanocrystals at P3HT/ITO interfaces have been investigated by modulated surface photovoltage SPV spectroscopy in a fixed capacitor arrangement The SPV measurements were correlated with the crystalline sizes of P3HT nanocrystals determined by grazing incidence Xray diffraction GIXRD The crystalline sizes of P3HT nanocrystals were varied systematically by progressive heating/cooling cycles identical for SPV and GIXRD measurements Photovoltage signals indication of photoinduced charge dissociation in space at the P3HT/ITO interface were collected and electrons were separated across the first monolayer of P3HT nanocrystals at the P3HT/ITO interface due to band bending The activation energies for quenching of the inphase and phaseshifted by 90° SPV signals were 07 and 06 eV respectively Thermal activation of the formation of P3HT nanocrystals was of the same order as the enthalpy of fusion of ideal crystals from regioregular P3HT A schematic drawing of photoinduced charge separation at the P3HT/ITO is proposedNR is grateful to the Higher Education Research Promotion and National Research University Project of Thailand Office of the Higher Education Commission and to TD for financial support to the University of Delaware for providing the infrastructure for GIXRD measurements at the Advanced Material Characterization Lab and to Gerald Poirer for technical support in the GIXRD measurements TS is grateful to the Kasetsart University Research and Development Institute LM 858 for financial support
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