First Principles Identification of Reaction Mechanism for Co Oxidation Over Low Dimensional Catalysts

Abstract

Metal-based catalysts are essential for the manufacture of chemicals, the refinement of fuels, and the clean-up of environmental pollutants. Their increasing demand and high cost diverting the quest towards the search of low cost and highly efficient catalyst for automobiles with less metal loading. To convert the hazardous pollutants (specifically CO) into less toxic substituents, a suitable catalyst with high catalytic life time, high catalytic activity and low CO poisoning is still a problem to be solved. CO oxidation in presence of oxygen is identified as the most suitable method for the conversion of CO. However, it is still not fully understood how atomic-scale processes result in the beneficial reactive properties of catalyst material. In this thesis, an attempt has been made to design a promising catalysts for catalytic oxidation of CO with less usage of metal atoms and high production rate i.e. following Langmuir-Hinshelwood mechanism. The mechanism of CO oxidation on nanostructured catalysts is thoroughly investigated. An ideal pathway is described over metal nanoalloys for CO oxidation. Role of bonding environment, surface structure, and Sabatier activities are also researched. It is also noted that modifying the surface structure can make it possible to modify the CO oxidation pathway. An electronic and energy descriptors are defined to search a most prominent catalyst and their catalytic activities. These surface-level analyses of catalytically active materials can help rationally design novel catalysts for more effective and environmentally friendly chemistry. newline