Final Activity Report Summary - NEWGROWTH (Newgrowth in the EU chemicals and technology sector through industry led training in nano-materials, catalysis, chemical engineering and atomistic modelling) Project NEWGROWTH allowed the establishment of a mono-partner inter-related group training hub at Johnson Matthey (JM) in the areas of nano-chemistry, materials synthesis, and catalysis and modelling. Six Marie Cure Fellows undertook career oriented PhD programmes aimed to emphasise the links between academia and industry. The main objectives were to yield improvements in the utility, energy efficiency and understanding of chemical industry processes and catalysts. These objectives were achieved through an array of inter-disciplinary approaches, including development of novel synthetic routes, computer modelling of nano-particle / support as well as macro-scale particle / particle interactions and catalyst testing.Fellow 1 designed and prepared a range of active palladium containing mixed metal oxide (titanate and manganate perovskites) catalysts for the direct formation of hydrogen peroxide from hydrogen and water. Hydrogen peroxide is an increasingly important and environmentally benign oxidant and offers a chlorine free alternative for bleaching in the paper industry.Fellow 2 was the first of two conducting research in the area of 'core-shell' nano-particle preparation in which a shell of one metal is deposited on a core of another. Such core-shell nano-particles are of significant interest as they offer unique properties. New synthetic routes to gold core - silver / palladium shell catalysts have been prepared. In addition, core-shell systems have been fabricated using particles of different morphologies, such as spheres, rods and wires. The new palladium-based systems were tested for liquid phase hydrogenation reactions and delivered enhanced activities and selectivities in chemoselective transformations.Fellow 3, also working with core-shell systems, used controlled surface reaction techniques to deposit platinum on to palladium and iridium nano-particles for use in fuel cell catalysts. The aims were to obtain active and durable catalysts with reduced platinum content thus enhancing the commercialisation prospects of this technology. Electrocatalytic activity measurements revealed core shell systems to be more active than pure platinum catalysts.Fellow 4 carried out a series of nano-scale coatings of supported precious metal particles with reducible metal oxides (ceria and vanadia). Striking observations linking the work function of the precious metal with the reducability and structure of the metal oxide coating were made. These represent a serious advancement in the understanding of such interactions, which have been extensively debated in the chemical literature, and yielded improved alkane combustion catalysts.Fellow 5 undertook atomistic computer modelling studies to assess the interactions between catalytically important metal nano-clusters (Ni, Pd, Pt and Au) and surfaces of alumina, a very common catalyst support material. The nature of these interactions distinctly alters the chemistry of the nano-clusters and in turn affects catalytic performance. The effect of varying amounts of surface water (which will be present in many real systems) was assessed and this revealed that the metal is stabilised by hydroxyl groups on the alumina surface and the formation of a metal hydride phase. In addition to this the adsorption and activation of CO was investigated. Fellow 6 modelled the interactions found within a large bed of millimetre sized particles as they were mixed. The interactions are typical of those found during the industrially important and multi-stage process of catalyst preparation. After assessing the suitability of commercially available discrete element modelling (DEM) software for this task suitable models were then built and validated. Validation was by comparison with the literature and bespoke experimental data obtained using an advanced radioactive particle tracking technique. An explanation of the main mixing / segregation regimes and mechanisms was derived.
