A Broadband Phototransistor Based on Three-Dimensional Reduced Graphene Oxide Foam

Three-dimensional (3D) cross-linked polymer-like reduced graphene oxide foams (rGOFs) with a seamlessly continuous graphene network, exhibit high photoresponsive and conductivity and have received much attention regarding solar cells and supercapacitors. However, little attention has been paid to photodetection applications of 3D rGOFs. Here we report a novel broadband phototransistor based on metal-3D GFs-metal, which exhibits a high light absorption and a wide spectra response ranging at least from 400 to 1600 nm wavelength with a maximum photoresponsivity of 10 mA/W at 400 nm. In particular, stable and reproducible photocurrent cycles are achieved under different light blue light (405 nm), green light (532 nm), and NIR (808 nm) irradiations. Moreover, the device displays a typical transistor characteristic with a rapid response time of 18 ms at under 532 nm irradiation. The excellent performances indicate 3D rGOF as a promising candidate for future photodetection application.