Hybrid framework materials such as metal organic frameworks (MOFs) or polyoxometalates (POMs) have received a lot of attention as building blocks for new multifunctional materials due to their wide range of magnetic, redox, and catalytic properties. Polyoxometalate-based metal organic frameworks (POMOFs) are built from the connection of POMs to one another through bridging organic linkers. 3D structures are uncommon.

Caroline Mellot-Draznieks and colleagues, University Joseph Fourier, Grenoble, France, have synthesized and characterized a series of novel POMOFs containing monomeric, dimeric, or chain-like Zn-ε-Keggin (ε-PMo^V₈Mo^VI₄O₃₆(OH)₄Zn₄) building blocks connected by trimesate ions. The 3D open-frameworks have channels occupied by tetrabutylammonium counterions.

The new POMOFs were tested as catalysts for the hydrogen evolution reaction and their performances exceeded that of platinum, giving yields over 95 %.

• Polyoxometalate-Based Metal Organic Frameworks (POMOFs): Structural Trends, Energetics, and High Electrocatalytic Efficiency for Hydrogen Evolution Reaction
  B. Nohra, H. E. Moll, L. M. Rodriguez Albelo, P. Mialane, J. Marrot et al.,
  J. Am. Chem. Soc. 2011.
  DOI: 10.1021/ja201165c