Björn Eckhardt

Micelle‐Templated Mesoporous Films of Magnesium Carbonate and Magnesium Oxide

Many industrial, chemical and catalytic processes rely on oxides of alkaline-earth metals with high surface area. Among these oxides, magnesium oxide serves e.g. as cement additive, fi re resistant insulation as well as for adsorption and deacidifi cation in the rubber industry. Due to its unique surface chemistry, MgO is also employed as catalyst support (oxidation of CO on Gold, [ 1 , 2 ] dehydrogenation/dehydration reactions [ 3 ] ) and as catalyst with basic surface properties. Moreover, MgO-based catalysts are promising candidates for the oxidative coupling of methane (OCM), which has been proposed as a key-technology to overcome the dependency on petroleum of many branches of the chemical industry. [ 4 , 5 ]

Versatile control over size and spacing of small mesopores in metal oxide films and catalytic coatings via templating with hyperbranched core–multishell polymers

Controlling the pore structure of metal oxide films and supported catalysts is an essential requirement for tuning their functionality and long-term stability. Typical synthesis concepts such as “Evaporation Induced Self Assembly” rely on micelle formation and self assembly. These processes are dynamic in nature and therefore strongly influenced by even slight variations in the synthesis conditions. Moreover, the synthesis of very small mesopores (2–5 nm) and independent control over the thickness of pore walls are very difficult to realize with micelle-based approaches. In this contribution, we present a novel approach for the synthesis of mesoporous metal oxide films and catalytic coatings with ordered porosity that decouples template formation and film deposition by use of hyperbranched core–multishell polymers as templates. The approach enables independent control of pore size, wall thickness and the content of catalytically active metal particles. Moreover, dual templating with a combination of hyperbranched core–multishell polymers and micelles provides facile access to hierarchical bimodal porosity. The developed approach is illustrated by synthesizing one of the most common metal oxides (TiO2) and a typical supported catalyst (PdNP/TiO2). Superior catalyst performance is shown for the gas-phase hydrogenation of butadiene. The concept provides a versatile and general platform for the rational optimization of catalysts based e.g. on computational prediction of optimal pore structures and catalyst compositions.