One-pot low-energy synthesis of rGO-CuO hybrid for detection of NO2 at room temperature

Abstract We reported a mild one-step co-precipitation method to synthesis reduced graphene oxide (rGO-CuO) hybrid at room temperature. It is a low-energy consumption as well as eco-friendly method and shows great advantages in preparation of rGO-based nanocomposites. The CuO nano-leafs wrapped by rGO nanosheets results in the rGO-CuO hybrid which exhibits a fluffy framework structure. When employed in a gas sensor device, the hybrid demonstrates an ultra-sensitive behavior and performs a ∼6.3 response within 30 s–100 ppb NO2 gas at room temperature. The influence of humidity on sensing performance of the as-prepared rGO-CuO sensor has been systematically investigated. The excellent sensing behavior can be attributed to the surface pre-adsorbed OH−/H2O, rough surface of the CuO nano-leafs and the constructed fluffy framework structure of rGO-CuO hybrid. Such a facile strategy not only provides new ideas for low-power synthetic composites, but also offers an important reference for developing of highly sensitive room temperature sensors.