Iron phosphates are of interest because of rich crystal chemistry and practical applications. New crystalline iron phosphates have been prepared in aqueous or predominantly nonaqueous solvents under mild hydrothermal conditions using organic amines as structure-directing agents. The effects of pH, solvent, and temperature on the reaction products are discussed. FePOs have been prepared with 1-D chain, 2-D layered, and 3-D open framework structures. An FePO containing a chiral amine is also synthesized. This review will summarize some of the results of the work in the area of organically templated iron phosphates.

The development of zeolite-like structures with extra-large pores (>12-membered rings, 12R) has been sporadic and is currently at 30R. In general, templating via molecules leads to crystalline frameworks, whereas the use of organized assemblies that permit much larger pores produces noncrystalline frameworks. Synthetic methods that generate crystallinity from both discrete templates and organized assemblies represent a viable design strategy for developing crystalline porous inorganic frameworks spanning the micro and meso regimes. We show that by integrating templating mechanisms for both zeolites and mesoporous silica in a single system, the channel size for gallium zincophosphites can be systematically tuned from 24R and 28R to 40R, 48R, 56R, 64R, and 72R. Although the materials have low thermal stability and retain their templating agents, single-activator doping of Mn(2+) can create white-light photoluminescence.

A nanoporous zinc gallophosphate framework, NTHU-4, possessing 14-ring channels, disordered rims, and two luminant analogues, NTHU-4Y and NTHU-4W, has been synthesized and characterized; NTHU-4Y is an intrinsic yellow phosphor, while NTHU-4W is a white phosphor. The unique tetrahedral framework can be excited by wavelengths longer than 254 nm to give intense yellow-to-white luminescence. Subtle changes in disorderliness were observed to be related to the distinct photoluminescence property.

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