Effect of Substrate on the Photodetection Characteristics of ZnO-PAni Composites

摘要

Heterojunction photodiodes involving a wide bandgap semiconductor on polymeric substrates have a number of potential advantages such as excellent blue response, simple processing steps, and low processing cost. We report on the chemical synthesis of ZnO-polyaniline (PAni) composite thin films and their use for UV detection. The morphological and structural properties of the composites were characterized using X-ray diffraction (XRD), Raman spectroscopy, and field-emission scanning electron microscopy (FESEM). The XRD results demonstrated the formation of hexagonal wurtzite ZnO structure, with no noticeable change upon the addition of PAni. The FESEM images revealed the hexagonal microstructure of the ZnO-PAni composite films, with high porosity. Raman spectroscopy revealed the interfacial interaction between ZnO and PAni. Thin films deposited on glass, PET, and Si substrates were used to fabricate photodetector devices based on the ZnO-PAni composites. The photodetector made using Si substrate showed the best performance with a high gain of 108, sensitivity of 9842, and responsivity of 0.707A/W. (C) 2016 The Electrochemical Society. All rights reserved.