Synthesis and Gas-Sensing Properties of MnO2 – x and MnO2 – x/CuO-Coated Multiwalled Carbon Nanotube Nanocomposites

Resumo

Nanocomposites based on multiwall carbon nanotubes (MWCNTs) impregnated with manganese oxide MnO_2 – x and copper oxide CuO are synthesized and studied. The morphology and elemental composition of MWCNT layers and MWCNT/MnO_2 – x and MWCNT/MnO_2 – x/CuO nanocomposites are investigated by scanning electron microscopy and X-ray photoelectron spectroscopy. We study the gas-sensing response of the prepared nanocomposites to hydrogen sulfide (H₂S) and nitrogen dioxide (NO₂). An increase in the conductance observed for the as-grown MWCNTs and the nanocomposites upon NO₂ adsorption suggests that these structures exhibit a behavior characteristic of p-type conductivity. Nanocomposites with copper show a markedly enhanced gas-sensing response to H₂S.