Building a complex structure system of conductive polymers without a complicated fabricating process is a long-awaited goal to improving the functional photoresponse properties of conductive polymers. In this study, we demonstrate that the photoresponse of polypyrrole (PPy)-based photodetector devices with an ultrathin polymer layer can be chemically modulated by simply immersing the devices into an alkaline solution. After alkaline treatment, the pyrrole unit transforms into a quinoid structure. Characteristics of current-voltage reveal an increased photosensitivity with several orders of magnitude when decreasing the applied bias voltage. Furthermore, ultrathin PPy belts with a width of 100 nm exhibit ultra-high photosensitivites of roughly 1000 (unit) and photoresponsivities of 54.3 A W-1 due to the high surface area ratio of the nanobelts.
Bibliographical noteFunding Information:
This study was supported by the National Natural Science Foundation of China (Project Code, 21373144), the International Collaboration program granted by Chinese Ministry of Science and Technology (2016YFE0129800) and the National Research Foundation of Singapore (CREATE Programme of Nanomaterials for Energy and Water Management). This is also a project supported by the Natural Science Foundation of Jiangsu Province (Project Code, BK20150007 and BK20151228); the Natural Science Foundation in High Education of Jiangsu Province (16KJB430024); and project funded by Collaborative Innovation Center of Suzhou Nano Science & Technology, the 111 Project, and the Priority Academic Program Development of Jiangsu Higher Education Institutions (PAPD).
© 2017 The Royal Society of Chemistry.