Ultra-efficient room-temperature H2S gas sensor based on NiCo2O4/r-GO nanocomposites

NiCo2O4/r-GO nanocomposites were obtained using hydrothermal synthesis, followed by an annealing treatment. The products were examined by XRD, FESEM, TEM, and XPS, which indicated that the NiCo2O4/r-GO nanocomposites were synthesized successfully. For exploring their potential applications in the gas detection field, gas sensors were fabricated by employing the NiCo2O4/r-GO nanocomposites and explored for their sensing ability towards H2S at room temperature. It could be found that the NiCo2O4/r-GO nanocomposites exhibited a relatively high response of 3.51 and very short response time of 2 s when exposed to 100 ppm of H2S, which were higher and faster, respectively, than those of pure NiCo2O4. Moreover, the reasons for the enhancement in the sensing properties by combining with r-GO were also discussed.