Synthesis of large single crystal of ZnAlPO4-15 by using melamine as structure directing agent

We report effects of crystallization conditions and gel composition on the hydrothermal synthesis of large zinc-doped AlPO 4 -15 (ZnAlPO 4 -15) single crystals by using melamine (MA) as structure directing agent (SDA). By optimizing the following synthesis conditions: amount of MA, molar ratio of ZnO/Al 2 O 3 , molar ratio of P 2 O 5 /Al 2 O 3 , crystallization temperature and duration, the pure phase of ZnAlPO 4 -15 (size up to 95 μm) with good optical transparency can be obtained at 200 °C with 40 h in the system of Al 2 O 3 :1.07MA:0.27ZnO: 1.15P 2 O 5 :667H 2 O. To the best of our knowledge, it is the first report of synthesizing ZnAlPO 4 -15 by using MA as SDA.