Preparation, characterization and gas sensing properties of sub-micron porous WO3 spheres

Abstract In this paper, sub-micron porous WO3 spheres with uniform size were firstly prepared by the hydrolysis of WCl6 using carbon microspheres as templates in the hydrothermal system and the following heating treatment. The carbon template, precursor, and the final products were characterized by XRD, SEM, TEM and BET analysis. The as-prepared sub-micron porous WO3 spheres had a large diameter of about 200 nm, which is critically determined by the size of carbon templates and WO3·H2O/C precursor. In addition, these porous spheres have a large porosity and exhibit high gas sensitivity to alcohol in different concentrations. The facile preparation method and the improved properties derived from the porous spheres structures are significant in the synthesis and future applications of functional nanomaterials.