tailieunhanh - Báo cáo hóa học: " Monitoring Charge Exchange in P3HT-Nanotube Composites Using Optical and Electrical Characterisation"

Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành hóa học dành cho các bạn yêu hóa học tham khảo đề tài: Monitoring Charge Exchange in P3HT-Nanotube Composites Using Optical and Electrical Characterisation | Nanoscale Res Lett 2009 4 635-639 DOI S11671-009-9287-9 NANO EXPRESS Monitoring Charge Exchange in P3HT-Nanotube Composites Using Optical and Electrical Characterisation Ioannis Alexandrou Emmanouil Lioudakis Dimitrios Delaportas C. Z. Zhao Andreas Othonos Received 16 September 2008 Accepted 5 March 2009 Published online 19 March 2009 to the authors Abstract Charge exchange at the bulk heterojunctions of composites made by mixing single wall nanotubes SWNTs and polymers show potential for use in optoelectronic devices such as solar cells and optical sensors. The density total area of these heterojunctions is expected to increase with increasing SWNT concentration but the efficiency of solar cell peaks at low SWNT concentrations. Most researchers use current-voltage measurements to determine the evolution of the SWNT percolation network and optical absorption measurements to monitor the spectral response of the composites. However these methods do not provide a detailed account of carrier transport at the concentrations of interest . near or below the percolation threshold. In this article we show that capacitancevoltage C-V response of metal - oxide - semiconducting composite devices can be used to fill this gap in studying bulk heterojunctions. In an approach where we combine optical absorption methods with C-V measurements we can acquire a unified optoelectronic response from P3HT-SWNT composites. This methodology can become an important tool for optoelectronic device optimization. I. Alexandrou El D. Delaportas C. Z. Zhao Electrical Engineering and Electronics University of Liverpool Liverpool L69 3GJ UK e-mail ioannis@ E. Lioudakis A. Othonos Department of Physics Research Center of Ultrafast Science University of Cyprus . Box 20537 Nicosia 1678 Cyprus E. Lioudakis Energy Environment and Water Research Center The Cyprus Institute . Box 27456 Nicosia 1645 Cyprus Introduction Composites of polymers and nanotubes have attracted much .