NCHU-3: a crystalline inorganic-organic hybrid molecular sieve with extra-large cages.

Abstract

Since the discovery of aluminophosphate VPI-5,[1] the synthesis of new crystalline large-pore zeolite-analogue materials with diameters of larger than 10 ! has been an important goal because of the diverse applications of these materials as nanoreactors, biosensors, and in nanotechnology.[2–5] Considerable attention has been directed towards the associated inorganic–organic hybrid architectures that, because of the incorporation of organic functional groups within a solid state inorganic framework, promise access to an even wider range of applications, such as altering the expected shape-selective influence in molecular sieves and hydrocarbon transformations.[6–11] To date, however, relatively few examples of wellordered crystalline solids with both large and hybrid pores are known.[12] Herein, we describe a novel nanoporous organophosphonate that contains both vanadium and gallium centers, [Ga2(VO)3K2(OH2)3(C2H4P2O6)4(H2O)13], which we have called NCHU-3 (National Chung-Hsing University-3). Pale-blue crystals of NCHU-3 were grown from a reaction mixture of KOH, Ga2O3, V2O5, ethylenediphosphate, and