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.

In this study, we synthesized a unique inorganic framework bearing the largest 18-membered-ring channels in gallium phosphites, denoted as NTHU-15, which displayed genuine porosity even though large organic templates were present. The idea of using the "template-cladded" strategy succeeded in releasing channel space of up to ∼24% of the unit-cell volume as highly positive-charged organic templates were manipulated to cling to the anionic inorganic walls. NTHU-15 showed both high H2 uptake of 3.8 mmol/g at 77 K and effective CO2 adsorption of ∼2.4 mmol/g at 298 K, which surpassed those of all other known extra-large-channel inorganic framework structures. NTHU-15 has been successful at overcoming the long-standing problem of organic-templated extra-large-channel structures as opposed to a "true open" framework. Moreover, it realized practical gas sorption functionality in innovated metal phosphites. In view of its high stability in hot water and high selectivity for CO2 adsorption, NTHU-15 may be the first novel inorganic framework material to be applied to the field of flue gas cleaning.