Hydrogen response of palladium nanoparticles washed with different solvents

Hydrogen sensor response of palladium (Pd) nanoparticles changes when the nanoparticles are washed with different solvents prior to device formation. This study presents the effect of washing Pd nanoparticles with distilled water or ethanol on their hydrogen response. The change induced in the surface characteristics of the Pd nanoparticles after washing is analysed with the help of UV–Vis absorption spectroscopy and glancing angle X-ray diffraction (GAXRD) studies. The nature of strain in nanoparticles after washing is particularly analysed from GAXRD data to understand the hydrogen response mechanism. The performance of the nanoparticle-based devices in humid ambient was also studied and the results were correlated to the consequence of sample washing. A suitable sensing mechanism within the purview of Langmuir model is discussed to understand the role of washing of the palladium nanoparticle yield.