Pulse like hydrogen sensing response in Pd nanoparticle layers

This study reports an enhanced and unusual pulse like hydrogen sensing response in Pd nanoparticle layers. The faster H adsorption due to increased surface area and closure of conducting paths as a result of lattice expansion on hydride formation are the primary reasons for this. In comparison, Pd thin films exhibit a slow and subdued sensing response because of the overlap of the above two opposing effects and hydrogen induced lattice strain. Temperature independent conductivity in the temperature range of 20–300K confirms the presence of interparticle gaps in the case of Pd nanoparticle layers.