Photoconductive Properties of MEH-PPV/CuS-Nanoparticle Composites

Photoconductive properties of photodiodes based on composites of CuS nanoparticles and Poly2-methoxy,5-(2’-ethylhexyloxy)-p-phenylenevinylene (MEH-PPV) are investigated. By comparing composite devices with different MEH-PPV:CuS weight ratios of 1:1 (D_2-1), 1:1.25 (D_2-2), 1:2.5 (D_2-3) and 1:5 (D_2-4), it is found that the device D_2-3 exhibited the best performance: the short-circuit current density of 17μA/cm² with the light intensity of 16.7 mW/cm², the highest open-circuit voltage of 0.83V, and the photosensitivity of 132 at reverse bias of -1 V. The photosensitivity is improved by a factor of 5 compared with the undoped MEH-PPV device.