Influence of pH values on WO3 nanomaterials during hydrothermal synthesis and its gas-sensing properties

摘要

As a promising gas-sensing material, tungsten tri-oxide with a wide band gap has attracted much attention. However, the preparation of tungsten tri-oxide nanomaterials in alkaline solution faces difficulties because of the weak solubility of the tungsten source. Here, the influence of pH values on the final products was investigated in detail. The results showed that pH value played no role in the phase for the final product. However, it had an obvious impact on the morphology evolution. Gas-sensing properties showed that the sensitivity increased with the increase of synthesised time because of improved crystallinity. Moreover, the sensitivity of the product synthesised in an alkaline environment was obviously higher than that of the product synthesised in an acid environment.