Crumpled graphene prepared by a simple ultrasonic pyrolysis method for fast photodetection

In the past decades, graphene has attracted much attention as the host material of photodetectors (PDs), owing to its fascinating mechanical property, ultrahigh carrier mobility and remarkable optical transparency. However, the intrinsic low light absorption of graphene affects its comprehensive application in PDs. Therefore, graphene-based PDs research has focused on hybrid system and optimized graphene structures to enhance photoabsorption. In order to combine the advantages of both approaches, we successfully prepared crumpled reduced graphene oxide (C-rGO) for PDs by a simple ultrasonic pyrolysis method. Through this rapid, one-step capillary-driven route, C-rGO and C-rGO/(ZnO, PbS) composite films can be easily deposited on arbitrary substrates (PET, glass, Al2O3 ceramic and paper). Interestingly, the unique C-rGO PDs shows superior stability and fast transient photocurrent response (rise/decay time of 189/189 ms). Furthermore, by incorporating ZnO and PbS nanoparticles to enhance light absorption, the crumpled hybrid nanostructure PDs demonstrate about four times increased photocurrents and broad-band (UV-Vis-NIR) photodetection features with R of 0.12 A/W. Such crumpled C-rGO-based PDs hold great potentials for future optoelectronic applications, and the ultrasonic pyrolysis method could open a new way for engineering novel nanostructured thin films with high-performance photodetection. (C) 2017 Elsevier Ltd. All rights reserved.