ZnO as functional material for sub-ppm acetone detection

Zinc oxide nano-powders with different morphologies have been synthesized using a wet chemical route, starting from an aqueous solution of Zn(NO<inf>3</inf>)<inf>2</inf>o 6H<inf>2</inf>O. The obtained powders shaped like nanoparticles, bipyramidal nanoaggregates, nanoneedles and flower-like nanostructures. The screen-printing technique has been adopted to deposit the functional materials in form of thick films onto miniaturized alumina substrates or onto silicon substrates for PL measurements. Acetone, acetaldehyde, formaldehyde, ethanol and ammonia have been used as testing gases, highlighting that the bipyramidal samples exhibited the best performances versus all gases, but especially toward acetone at sub-ppm level.