A　new　solid　niobic　acid　phase,　H-2(H2O)Nb2O6,　with　fluorine　(F)　doping　was　crystallized　using　hydrothermal　chemistry.　F-doped　H-2(H2O)Nb2O6　octahedra　could　function　as　an　efficient　heterogeneous　catalyst　for　the　photodegradation　of　organic　pollutants　in　water　under　UV　light　irradiation.　The　high　photocatalytic　activity　of　the　F-doped　H-2(H2O)Nb2O6　materials　is　attributed　to　a　synergistic　effect　of　the　specific　surface　area,　the　surface　characteristics　and　the　crystal　structure.　Our　results　suggest　novel　ways　of　controlling　the　crystallization　of　niobium　oxides,　further　the　fundamental　understanding　of　their　structure-property　relationships,　and　may　lead　to　their　application　in　fields　such　as　environmental　protection　and　energy　production.