Synthesis of porous ZnO structure for gas sensor and photocatalytic applications

In this work, porous ZnO hexagonal nanostructure was synthesized via a simple precipitation method at a relatively mild temperature with Zn(Ac)2 and ammonia as reagents. The XRD and FE-SEM analysis indicated that the ZnO nanoparticles was hexagonal (wurtzite) structure with a size of 50–100 nm. The pore volume of the porous ZnO nanoparticles reached 0.6 m3/g and the pore size was mainly centered at ∼5 nm by N2 adsorption–desorption analysis. The porous ZnO product was used to construct a gas sensor for ethanol and acetone detection at different operating temperature, and the as-prepared ZnO gas sensor exhibited an excellent sensitivity and a short recovery time (several seconds) to ethanol and acetone gases, indicating its potential application as a gas sensor to detect ethanol and acetone. Moreover, the photocatalytic activity of ZnO nanoparticles on methyl orange (MO) was investigated through a UV–vis spectrophotometer, and the degradation ratio reached 99% after UV irradiation about 30 min, which indicated that the ZnO product showed a superior ultraviolet light catalytic activity.