Design of highly active Mo-V-Te-Nb oxide catalyst for ODH is made possible by understanding the formation of active surfaces
MoVTeNb oxide catalysts are used for ethylene production via ethane oxidative dehydrogenation (ODH). Maricruz Sanchez-Sanchez and Johannes A. Lercher at the CRC work on the optimization of this type of materials for an industrial application, in collaboration with Clariant AG in the frame of the MuniCat alliance.
In situ electron microscopy studies at the Pacific Northwest National Laboratory in collaboration with Nigel Browning and Yuanyuan Zhu have yielded the atomic description of the active surface of a metal oxide catalyst and its dynamic response under reaction conditions. These studies, combined with reaction kinetics measured at the CRC, provided a direct relationship between the atomic configuration of the surface of an oxide and its catalytic activity. This level of understanding has enabled the researchers to design a new synthetic approach that proved successful in generating highly active metal oxides. This work has been published in September 2019 in Nature Communications.
Ultrasmall Pt clusters derived from Pt@MOF materials for the oxygen reduction
The electrocatalytic oxygen reduction (ORR) using a platinum catalyst is considered as the key to many energy applications, such as fuel cell technologies. In a joint effort the teams of Aliaksandr Bandarenka, Roland A. Fischer and Sebastian Günther from the CRC, Alessio Gagliardi from the TUM Department of Electrical and Computer Engineering, and Jan Macák from the CEITEC in Brno (Czech Republic) have achieved a breakthrough in preparing ultrasmall Pt clusters with optimal size for the efficient electrocatalytic ORR in proton-exchange-membrane fuel cells by combining theory and experiment. The results were published online on June 5, 2019 in Angewandte Chemie International Edition.
By utilizing a simple computational model, the mass activity of Pt clusters for ORR was predicted. The forecasted activities were affirmed with the experimental results for 1.1 nm sized Pt clusters, which were obtained by decomposition of Pt clusters embedded in the zeolitic imidazolate framework ZIF-8. The obteined Pt clusters exhibit a mass activity of 0.87 A mgPt-1 , which is one of the highest mass activities reported to date.