The tunable mid-infrared source in a broad-spectrum heralds great scientific implications and remains a *** catalytic combustion facilitates access to customizable infrared light ***,we report on fabricating platinuma...
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The tunable mid-infrared source in a broad-spectrum heralds great scientific implications and remains a *** catalytic combustion facilitates access to customizable infrared light ***,we report on fabricating platinumalumina bilayer nano-cylinder arrays for methanol catalytic combustion,which enables them to act as an array of infrared point light sources,with wavelength tunable by controlling the flow rate of methanol/air *** then propose a technique of integrating nanophotonic structures with catalytic combustion to engineer infrared light *** demonstrate a prototype of a topological photonic crystal catalystarray in which infrared emission can be enhanced significantly with highly vertical *** work establishes a framework of nanophotonic catalytic combustion for infrared light sources.
Low temperature propane oxidation has been achieved by Co3O4-based nano-array catalysts featuring low catalytic materials loading (15 mg under flow rate of 150 mL/min). The increased Ni doping into the Co3O4 lattice h...
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Low temperature propane oxidation has been achieved by Co3O4-based nano-array catalysts featuring low catalytic materials loading (15 mg under flow rate of 150 mL/min). The increased Ni doping into the Co3O4 lattice has led to 100% propane conversion at low temperature (<400 degrees C) and has enhanced reaction kinetics by promoting the surface lattice oxygen activity. In situ DRIFTS investigations in tandem with isotopic oxygen exchange reveals that the propane oxidation proceeds via a Mars-van Krevelen mechanism where surface lattice oxygen acts as the active site whereas O-2 in the reaction feed does not directly participate in CO2 formation. The Ni doping promotes the formation of less stable carbonates on the surface to facilitate the CO2 desorption. The thermal stability of Ni doped Co3O4 decreases with increased Ni concentration despite the increased catalytic activity. A balance between enhanced activity and compromised thermal stability is considered in the Ni doped Co3O4 nano-array catalysts for hydrocarbon oxidation. This study provides useful and timely guidance for rational catalyst design toward low temperature catalytic oxidation. (C) 2015 Elsevier B.V. All rights reserved.
Monolithic catalyst, usually composed of honeycomb substrate and wash-coated powder-form catalysts on its channel surface, represents a unique class of functional devices that has been adapted in current industries, p...
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Monolithic catalyst, usually composed of honeycomb substrate and wash-coated powder-form catalysts on its channel surface, represents a unique class of functional devices that has been adapted in current industries, particularly in automotive industry as catalytic converters for engine emission aftertreatment purpose. The powder wash-coat based monolithic catalyst lacks well-defined structural configuration in particulate size, shape and distribution, leading to usually compromised materials utilization efficiency and catalytic activity. Thus, it is necessary to develop new generation of high performance monolithic catalysts to meet the increasingly stringent emission regulation. Perovskite materials have been studied as potential candidate of automotive catalysts for decades, with their excellent thermal stability and redox ability allowing them being promising catalysts for heterogeneous catalytic reactions at high temperature. In this dissertation, we introduce design and manufacturing of large-scale high performance ZnO/perovskite nano-array based monolithic catalysts. Detailed discussions are focused on catalytic activity enhancement via rational materials selection and structural manipulation. Noble metal incorporation, acid treatment effect and hydrothermal stability are further studied. The Pt incorporated catalysts exhibit good catalytic performance towards propane oxidation with good hydrothermal stability. The acid treated perovskite nano-array catalysts possess enhanced low temperature activity due to the evolution of nanostructure and surface chemistry. With the successful demonstration of industrially-relevant integration strategy, ZnO/perovskite nano-array catalysts show promise as a new type of monolithic catalysts for automotive emission control.
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