The missing link between zeolites and polyoxometalates

Abstract

Open framework materials such as zeolites and metalorganic frameworks are garnering tremendous interest because of their intriguing architecture and attractive functionalities. Thus, new types of open framework materials are highly sought after. Here, we present the discovery of completely new inorganic framework materials, where, in contrast to conventional inorganic open frameworks, the scaffold is not based on tetrahedral EO 4 (E = main group element) but octahedral MO 6 (M = transition metal) building blocks. These structural features place them closer to polyoxometalates than zeolites. The first representatives of this class of materials are [(R) 24 (NH 4 ) 14 (PO(OH) 2 ) 6 ]·[M 134 (PO 3 (OH,F)) 96 F 120 ] (M = Co, R = C 2 Py = 1-ethylpyridinium and M = Ni, R = C 4 C 1 Py = 1-butyl-3-methylpyridinium) featuring interlinked fullerene-like nanosphere cavities. Having a transition metal building up the framework brings about interesting properties, for example, spin-glass behavior, and, with this particular topology, a hedgehog-like spin orientation.

Atomically Precise Single-Site Catalysts via Exsolution in a Polyoxometalate–Metal–Organic-Framework Architecture

“…6 For example, in the case of the Anderson−Evans POM, which is formed by a plane of seven edge-sharing Mo-oxo octahedra (Figure 1a) and the central M site, within a ring of six MoO 6 octahedra, can be substituted by other transition metals, including Fe, Co, Ni, Cu, Rh, and Pt, to enable different catalytic reactions. 7−9 Recent efforts toward POM-based catalysis have dispersed them on high surface area supports, 10,11 such as porous silica and metal−organic frameworks (MOFs), 12,13 to enhance accessibility to the POM relative to the bulk. Here, the versatile tunability of MOF pore geometries and chemical environments 14 Zr.HVCDAMXLLUJLQZ.MOFkey-v1.csq) can exhibit higher catalytic reactivity than either component alone.…”

“…Recent efforts toward POM-based catalysis have dispersed them on high surface area supports, , such as porous silica and metal–organic frameworks (MOFs), , to enhance accessibility to the POM relative to the bulk. Here, the versatile tunability of MOF pore geometries and chemical environments combined with the versatility of POMs allows for both a high level of control over the SSC structure and chemistry and also an unmatched opportunity to explore how these govern catalysis.…”