CTAB assisted hydrothermal preparation of YPO₄:Tb³⁺ with controlled morphology, structure and enhanced photoluminescence

In this paper, we report a simple and convenient method toward fabrication of YPO₄:Tb³⁺ with controlled structures, morphologies and enhanced luminescent properties. By simply controlling the amount of the cetyltrimethyl ammonium bromide (CTAB) during the hydrothermal process, tetragonal YPO₄:Tb³⁺ and hexagonal YPO₄· 0.8H₂O:Tb³⁺ with nanoparticle and olive-like nanoparticle can be obtained, respectively. Meanwhile, we find that the structures and morphologies can affect their luminescent properties obviously and the intensity of the samples with hexagonal phase is evidently higher than that with tetragonal phase. The variation of crystal structures, morphologies of the samples are ascribed to the crucial role of CTAB during the fabrication process that acts as complexing reagent and inducing agent and the mechanism was also discussed. We believe the method reported here will open a novel approach to rare earth phosphates with multiple structures.