▎ 摘　　要

The sandwich-like composite of double-layer Co3O4 and reduced graphene oxide (rGO) is successfully manufactured through a one-step hydrothermal method. The gas sensing test results indicate that the sandwich-like composite of double-layer Co3O4 and rGO (D-Co3O4/rGO) has a five-fold increase in response to 100 ppm triethylamine compared to conventional Co3O4 sensor at the optimum working temperature of 200 degrees C. The higher response may be attributed to the double-layer structure of Co3O4 in the D-Co3O4/rGO which can effectively utilize the surface areas of Co3O4. It is also capable of detecting a minimum concentration of 1 ppm of triethylamine gas. (C) 2019 Elsevier B.V. All rights reserved.