Effect of phase structures of TiO2−xNy on the photocatalytic activity of CaAl2O4:(Eu, Nd)-coupled TiO2−xNy

Nitrogen-doped titanium oxide (TiO2−xNy) nanocrystalline with different phase of anatase, rutile or brookite was coupled with CaAl2O4:(Eu, Nd) particles by planetary ball milling treatment. The effect of phase structures on the persistent photocatalytic activity of a CaAl2O4:(Eu, Nd)/TiO2−xNy composite was evaluated for the oxidative destruction of NO. The persistent catalytic degradation of NO by TiO2−xNy was realized in the presence of CaAl2O4:(Eu, Nd), which shows a long afterglow luminescence. The persistent photocatalytic property of composites changed depending on the crystalline phase of TiO2−xNy, i.e., the persistent photocatalytic property of CaAl2O4:(Eu, Nd) combined with brookite type TiO2−xNy was superior to those of anatase or rutile phase TiO2−xNy.