Enhancement in gas sensing performance of MoO₃-loaded SnO₂ sensor via improving adsorption and partial oxidation

A surface functionalization route utilizing MoO₃-loading was employed to activate ethanol adsorption and partial oxidation on the surfaces of SnO₂ nanoparticles for use as highly sensitive ethanol sensors. STEM-EDS mappings verified that the majority of Mo ions were dispersed and doped into the lattice of the SnO₂ nanoparticles as foreign receptors. According to catalytic combustion measurements of ethanol on the SnO₂ surface, the MoO₃-loading process decreased the complete oxidation but improved the yield of intermediates by accelerating dehydrogenation at low temperatures (50–250 ℃). We evaluated the sensing properties in the double-pulse-driven mode using a microheater constructed via a micro-electronic-mechanical-system technique. The sensor response S_p to ethanol of the MoO₃-loaded SnO₂ microsensor, 496, was dramatically higher than that of the neat-SnO₂ microsensor, 3. The outstanding sensing performance was mainly attributed to the improved partial oxidation of ethanol and enhanced ethanol adsorption capacity due to the introduction of Mo ions. The results provide promising insights into the material design for highly sensitive ethanol detection by controlling gas adsorption and combustion.