Low temperatures and concentrations ethylene glycol sensing based on ultrathin graphene oxide-decorated CuO nanosheets

Ethylene glycol is a toxic contaminant, hence the monitoring of its vapor is crucial for environmental safety and human health. In this study, CuO/GO ultrathin nanosheet composites were successfully synthesized via a one-step chemical precipitation method, and subsequently used for the detection of low concentrations of ethylene glycol at low temperatures. The test results indicate that CuO/0.7GO shows a response of 39.5 at 110 °C for 10 ppm ethylene glycol, which is 19 times greater than that of CuO, and the optimal operating temperature reduced by 20 °C compared to CuO. Notably, CuO/0.7GO still demonstrates a response of 7.02 for 1 ppm ethylene glycol. Furthermore, the CuO/0.7GO sensor exhibits significant selectivity, repeatability, and long-term stability toward ethylene glycol. The morphology, microstructure, and elemental composition of the materials were characterized by XRD, SEM, TEM, EDX, FT-IR, XPS, and UV–Vis. Finally, the gas sensing mechanism of the composite material toward ethylene glycol was discussed in depth, emphasizing that the enhanced gas sensing performance was attributed to the synergistic effect between the abundant chemisorbed oxygen and the hybrid heterojunctions.