Surface oxygen atoms activated by Co metal sites enhanced the H2S gas sensing of Co-doped MoO3 nanoflowers

The inert gas adsorption of outer oxygen atoms is becoming an important factor limiting the gas sensing activity of two-dimensional MoO 3 nanoflowers, which makes it necessary to modify the surface activity of MoO 3 nanoflowers. For a long time, the unique activity of Co atoms has attracted much attention in gas sensing. In this work, Co metal sites were introduced into MoO 3 defective nanoflowers (MoO 3 DNFs) by doping, which further improved the H 2 S gas sensing performance of MoO 3 DNFs. Based on H 2 S gas sensing experiment, the relationship between Co doping amount and gas sensing performance was constructed, and the optimal Co doping ratio was obtained. Finally, the adsorption reaction process of H 2 S gas molecules on MoO 3 -Co DNFs was simulated by DFT calculation, and the activation effect of Co metal sites on outer oxygen atoms was revealed.