Increased sensitivity of amorphous carbon based gas-sensors due to different Au nanostructures.

We reported that gold nanoparticles attached with the amorphous carbon (a-C) could promote sp$^{\mathrm{2}}$ bonds around the gold nanoparticles. This can change the hopping characteristics and can control the carrier transport which results in increased conductivity. These nanocomposites exhibit a superior sensitivity towards NH$_{\mathrm{3}}$ at room temperature, as well as good reproducibility and short response/recovery time. To increase the sensitivity of gas-sensors we need to increase the interface effect between gold nanostructures and a-C. To increase this interface effect we choose gold nanorods instead of nanoparticles. To grow the gold nanorods along z-direction perpendicular to the substrate surface we use low temperature deposition technique. Improvement in the interfacial effect will greatly improve the sensitivity of gas-sensors.