preparation of different wo3 nanostructures and comparison of their ability for congo red photo degradation

tungsten trioxide nanoparticles with monoclinic structure and average particle size about 80 nm were prepared by the spray pyrolysis method. wo3 nanorods with hexagonal structure and average dimension about 15 × 100 nm were synthesized in gram quantities by modified hydrothermal method at lower temperature and shorter reaction time in comparison to the previous research. photo degradation of congo red showed that the as-prepared wo3 nanoparticles is more effective than nanorod structure. wo3 nanorods actually had no effect in congo red photo degradation. therefore in this reaction, spherical morphology is superior to column morphology. the samples were characterized with x-ray diffraction (xrd), scanning electron microscopy (sem), edx analysis, uv-visible spectrum and transmission electron microscopy (tem).