Two Cadmium Germanophosphates [CdGe(μ2 -O)(HPO4 )2 - (H2 O)2 ]. H2 O and Anhydrous Cd7 Ge(PO4 )6 : Syntheses, Crystal Structures and Photoluminescence Properties

Abstract

Two cadmium germanophosphates (GePOs), namely, [CdGe(μ2-O)(HPO4)2(H2O)2].H2O (1) and anhydrous Cd7Ge(PO4)6 (2) have been prepared by hydro/solvothermal method. Compound 1 crystallizes in a centrosymmetric (CS) space group P-1 with a 2D layer structure, which is composed of 1D [Cd(HPO4)4(H2O)2]∞ and [Ge(μ2-O)2(HPO4)4]∞ infinite chains. Compound 2 crystallizes in a centrosymmetric space group R-3 with a complicated 3D network, which is built from CdO6 octahedra, GeO6 octahedra and PO4 tetrahedra. TGA results showed that the structure of anhydrous Cd7Ge(PO4)6 was stable under 800 °C. The luminescent properties of two compounds were also investigated at room temperature. The color coordinate of 2 (0.2613, 0.2649) is close to that of the balanced white-light emission (0.333, 0.333), which indicates that compound 2 is a good blue light emitted material at room temperature under UV irradiation exaction, thus anhydrous compound 2 might be a potential candidate for blue light-emitted material.