International audienceWe investigate the effects of Si nanowires surface modification with polystyrene (PS) on the performance of bulk heterojunction hybrid solar cells based on poly[2-methoxy-5-(2'-ethylhexyloxy)-1,4-phenylene vinylene] (MEH-PPV) and PS-SiNWs. The optical, electrical and morphological properties of these hybrid nanocomposites have been investigated. Due to charge transfer efficiency, improved electrical coupling between SiNWs and MEH-PPV and homogeneous dispersion of functionalized SiNWs, the performance of studied photovoltaic structure shows a significant improvement with the progressive addition of PS-SiNWs. With polystyrene surrounded SiNWs as acceptor materials, the device typically shows a J(SC) of 7.36 mu A/cm(2), V...