Transfer-free and printable graphene/ZnO-nanoparticle nanohybrid photodetectors with high performance

Combining the high mobility of graphene and surface electron depletion effect of zinc oxide nanoparticles (ZnO-NPs), graphene/ZnO-NP nanohybrids can be anticipated for significantly enhanced photoresponsivity and photoconductive gain in optoelectronics. Herein, a transfer-free and printable method was developed for the fabrication of wafer-size graphene/ZnO-NP nanohybrids for high-performance UV photodetectors. These photodetectors achieved the extraordinary photoresponsivity of up to 1000 A W^-1 V^-1 and high gain of 1.8 × 10⁴, representing more than an order of magnitude improvement compared to that of previously reported UV photodetectors based on various ZnO nanostructures and transferred-graphene/ZnO nanohybrids. Our method provides a low-cost pathway for the run-to-run wafer-size fabrication of high-performance graphene/ZnO optoelectronics.