Engineering of spinels for catalysis

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The goal of the research program is to develop the technology of microwave or induction field assisted catalysis using magnetic spinels for heterogeneous gas-phase reactions. The innovation is to take advantage of the fact that only the reaction site on the nanoparticles needs to be at higher temperature to improve the efficiency and activity of surface reactions. Such process would enable fast heating to a given regeneration temperature and minimize sintering. The proposed 5-year research project intends to synthesize, characterize and study nanostructures of various spinel ferrites, namely MxFe3-xO4, with M = Ni, Co, Mn, Zn or mixture thereof. Being magnetic and susceptible to microwave, these nanomaterials are being considered as building blocks for producing hybrid nanostructures adapted for assisted catalysis. ***The ferrospinels will be produced using solution-spray thermal plasma, a technique well-established in our lab. The catalytic properties of the ferrospinels are known to be directly related to the affinity of the metals atoms towards specific sites of the spinel crystalline lattice. These metal-site interactions will be investigated using an array of complementary characterization methods, such as X-ray diffraction (XRD), X-ray fluorescence and electron microscopy.***The thermochemistry of these materials will be investigated using operando techniques, allowing the materials to be probed in working conditions to reproduce the behavior of spinels under reaction and design better spinels adapted to selected reactions. Using a gas flow cell, the change of the ferrospinels structure will be probed using operando XRD, X-ray absorption spectroscopy (XAS, at the Canada Light Source, Saskatoon), and thermogravimetry.***With the proposed metal spinels (Mn, Fe, Co, Ni, and Zn) so close in atomic number, finer details of the structure remain hidden from XRD analysis. However, a stronger contrast for these elements is expected if probed with neutron rather than X-rays. Another objective is to design and build an ambient station adapted to the beam line of the Canadian Institute for Neutron Scattering (CINS) in order to gain a comprehensive understanding of the gas/solid and solid-state interactions of these complex spinels during reaction.***The proposed research project is cornerstone to the long-term objective of the lab: the development of technologies based on novel hybrid materials. This research project covers the entire innovation cycle, from the design and synthesis of novel nanomaterials, to the proof of concept of an enabling technology.***The outcome of this research is expected to improve the energy efficiency of catalytic conversion processes by engineering novel nanomaterials and provide training in fields at the crossroads of nanomaterials science, chemical engineering and materials physics.