Outstanding Room-Temperature Hydrogen Gas Detection by Plasma-Assisted and Graphene-Functionalized Core–Shell Assembly of SnO₂ Nanoburflower

Here, we have reported the synthesis of three-dimensional, mesoporous, nano-SnO₂ cores encapsulated in nonstoichiometric SnO₂ shells grown by chemical as well as physical synthesis procedures such as plasma-enhanced chemical vapor deposition, followed by functionalization with reduced graphene oxide (rGO) on the surface. The main motif to fabricate such morphology, i.e., core-shell assembly of burflower-like SnO₂ nanobid is to distinguish gases quantitatively at reduced operating temperatures. Electrochemical results reveal that rGO anchored on SnO₂ surface offers excellent gas detection performances at room temperature. It exhibits outstanding H₂ selectivity through a wide range, from ∼10 ppm to 1 vol %, with very little cross-sensitivity against other similar types of reducing gases. Good recovery as well as prompt responses also added flair in its quality due to the highly mesoporous architecture. Without using any expensive dopant/catalyst/filler or any special class of surfactants, these unique SnO₂ mesoporous nanostructures have exhibited exceptional gas sensing performances at room temperature and are thus helpful to fabricate sensing devices in most cost-effective and eco-friendly manner.