Oxide vacancies enhanced visible active photocatalytic W19O55 NMRs via strong adsorption

W19O55 nano-/micron-rods (NMRs) were synthesized through calcining WO3 powders under a reducing atmosphere with S vapor in a vacuum furnace. For comparison, the as-prepared W19O55 NMRs were then annealed at 500 °C for 2 h to obtain WO3 NMRs. The decolourization of organic dyes methylene blue and rhodamine B under visible light by the two kinds of NMRs reveals that the oxygen-deficient W19O55 sample will present better comprehensive performance due to its stronger surface adsorption to the dye molecules, which could be attributed to the oxygen vacancies.