Solution-processed graphene phototransistor functionalized with P3HT/graphene bulk heterojunction

Here we present a feasible way to fabricate a high-performance graphene phototransistor functionalized with Poly(3-hexylthiophene) (P3HT)/graphene bulk heterojunction by solution processing, which possesses the advantages of the high carrier mobility of graphene and the high visible light absorption of P3HT. The hole field-effect mobility for the device was 3.8 cm2V−1s−1 at room temperature. The photoresponsivity, external quantum efficiency and detectivity were 12 A/W, 3 × 103 % and 1.6 × 106 Jones at a illumination irradiance of 15 mW/cm2 respectively. The phototransistor exhibited sensitive photoresponse with a rise time of 168 ms and a decay time of 121 ms.