Effect of Gold Nanoparticles Incorporation on Electrical Conductivity and Methane Gas Sensing Characteristics of Lead Sulfide Colloidal Nanocrystals

PbS nanocrystals (NCs) have recently shown the capability of room temperature sensing of some gasses like methane (CH4). Incorporation of silver nanoparticles (NPs) has been previously shown to improve methane sensing characteristics of PbS NCs. Gold (Au) is another noble metal, which is commonly used as additive to modify gas sensing properties of semiconductors. Here, in this paper, it is shown how the incorporation of an appropriate amount of Au NPs improves methane sensing characteristics of PbS NCs. Electrical conductivity, sensor response, and sensor speed are studied as a function of Au concentration (0%, 0.5%, 1%, 1.5%, and 2%). The best modifications were achieved by the addition of 1% Au into PbS NCs matrix.