BACKGROUND　Photocatalytic　degradation　of　organic　pollution　as　a　＇green＇　treatment　technology　has　been　a　broad　concern　in　water　treatment.　This　work　proposed　a　simple　method　for　introducing　oxygen　vacancies　into　WO3　and　enhancing　the　degradation　of　WO3　for　rhodamine　B　under　simulated　solar　light.RESULTS　In　this　work,　titanium　power　was　used　as　an　oxygen　absorber　to　introduce　oxygen　vacancies　into　WO3.　The　degradation　of　organic　dyes　by　semiconductor　materials　is　significantly　improved　by　the　presence　of　oxygen　vacancies.　After　4　h　of　simulated　sunlight　irradiation,　100%　degradation　efficiency　of　rhodamine　B　by　WO3　with　vacancies　was　achieved,　compared　to　about　60%　by　WO3.　Combined　with　liquid　chromatography-mass　spectrometry　and　total　organic　carbon　analysis　results,　we　speculated　the　degradation　path　of　rhodamine　B　degraded　by　WO3-2.CONCLUSION　There　exist　three　reasons　for　the　enhanced　photocatalytic　performance　of　oxygen-containing　vacancy　WO3:　(i)　the　introduction　of　vacancies　generates　an　energy　level　of　the　donor　that　can　reduce　the　band　gap;　(ii)　the　presence　of　oxygen　vacancies　can　effectively　prevent　the　electron-hole　complexation　process;　and　(iii)　oxygen　vacancies　increase　the　adsorption　capacity　of　the　catalyst.　It　is　expected　that　this　method　of　oxygen　vacancy　introduction　can　be　extended　to　other　semiconductor　systems　to　achieve　higher　performance　in　pollutant　degradation　and　water　remediation.　(C)　2023　Society　of　Chemical　Industry　(SCI).