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Abstract: Three types of Eu3+-doped LaPO4 three-dimensional (3D) microstructures have been hydrothermally prepared by adjusting pH value and the molar ratio of La3+ and Eu3+ to phosphorus of Na5P3O10 (Ln/P) at 180°C. As the pH value was 0.15 and the molar ratio of Ln/P was in the range of 1/1 to 1/4, 5μm urchinlike spheres composed of long nanorods of hexagonal LaPO4:Eu were obtained. As the pH value was 1.00 and the molar ratio of Ln/P was 1/1, 3μm hollow spheres consisting of short nanorods of monoclinic LaPO4:Eu were prepared. Keeping the pH value at 1.0 and the molar ratio of Ln/P at 1/4, 6μm core–shell spheres of monoclinic LaPO4:Eu formed. Luminescent measurements were performed. Hollow spheres of monoclinic LaPO4:Eu had the strongest emission intensity. However, the emission intensity of monoclinic core/shell structure was even lower than that of hexagonal LaPO4:Eu urchinlike spheres. [ABSTRACT FROM AUTHOR]

A new MnOOH precursor route has been developed to synthesize single-crystalline nanorods of tetragonal β-MnO2. Uniform γ-MnOOH nanorods were first prepared by reducing KMnO4 with KI under hydrothermal conditions at 120 °C. After calcination of the γ-MnOOH nanorods at 250 °C for 2 h in air, β-MnO2 nanorods retaining the morphologies of γ-MnOOH nanorods were obtained. The temperature, time and heating speed of calcination were found to be important for the morphologies of the β-MnO2 nanorods. [Copyright &y& Elsevier]