Investigation on the Photoconductive Properties of MEH-PPV/CdSe Nanocomposite Devices
TANG Ai-wei, TENG Feng*, GAO Yin-hao, JIN Hui, LIANG Chun-jun, XU Zheng, WANG Yong-sheng
Institute of Optoelectronic Technology and Key Laboratory of Luminescence and Optical Information, Ministry of Education, Beijing Jiaotong University, Beijing 100044, China
Abstract：Photoconductive properties of the composite devices made up of cadmium selenide nanocrystals and polymer poly[2-methoxy-5-(2′-ethylhexyloxy-p-phenylenevinylene)](MEH-PPV) were investigated. The photocurrent action spectrum for a nanocomposite device corresponded to the absorption of MEH-PPV and CdSe nanocrystals, indicating that the absorption of the CdSe nanocrystals and MEH-PPV contributed to the photocurrent. The photocurrent was attributed to the exciton dissociation and charge transfer between the interface of CdSe nanocrystals and MEH-PPV. The photocurrent action spectra of the nanocomposite device was wider than that of the pure MEH-PPV device, and the photocurrent was enhanced in comparison with the pure MEH-PPV device due to the introduction of CdSe nanocrystals.
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