Packing of Cylindrical Keggin-Type Polyoxometalate Hybrid Micelles as a Function of Aspect Ratio

Electrostatic attraction of nanoobjects – a versatile strategy towards mesostructured transition metal compounds

This highlight summarizes current challenges of mesostructuring and focuses on the scope and the potential of the ELAN – (electrostatic attraction of nanoobjects) strategy in mesostructuring of transition metal compounds.

Template Removal via Boudouard Equilibrium Allows for Synthesis of Mesostructured Molybdenum Compounds

Oxidative thermal removal of the polymeric templates is not trivial for molybdenum oxides and hampers mesostructuring of this material. At ambient oxygen fugacity, Mo^VI is the thermodynamically stable oxidation state and sublimation of MoO₃ leads to a quick loss of the mesostructure through Oswald ripening. Taking advantage of the Boudouard equilibrium allows to fix the oxygen fugacity at a level where non-volatile MoO_2-x is stable while carbonaceous material may be oxidized by CO₂ . Mesostructured MoO_2-x can be chemically converted into MoO₃ or MoN under retention of the mesostructure.