Synthesis and Characterzation of Doped Cerium Oxide Nanocomposites and Their Catalytic Application

Abstract

CeO2 is a highly promising catalytic material for a wide range of applications because of two distinctive characteristics: (a) the Ce4+/Ce3+ redox couple, which enables material transition between CeO2 and CeO2and#8722;and#948; in oxidizing and reducing environments, respectively, and (b) enhanced oxygen transport capacity, which facilitates the formation of oxygen vacancies. Pure CeO2, despite its numerous applications, is plagued by severe performance degradation over time when exposed to elevated temperatures. Elevated operating temperatures induce a swift sintering process in CeO2, resulting in impairment of the oxygen buffer capacity of the catalyst and eventual deactivation. Furthermore, the participation of lattice oxygen in redox reactions is negligible (and#948;~0.05), rendering pure ceria impractical for real-world applications. newlineIn this study we have synthesized pure and doped CeO2 nanoparticles by green synthesis approach using orange peel extract. The synthesized materials have been employed for soot oxidation activity under loose contact condition. The synthesized materials have been characterized using X-Ray diffraction (XRD) analysis for identifying the phase of the materials and data was used to calculate crystallite size, microstrain, and dislocation density. The morphological analysis was done by field emission scanning electron microscopy (FE-SEM) and elemental analysis was done by energy dispersive X-ray (EDX) spectroscopy. The identification of functional group present in the materials was done by Fourier Transform Infrared (FT-IR) Spectroscopy. The thermogravimetric and differential calorimetry (TGA-DSC) analysis was used to study soot oxidation activity. newlineChapter 1 introduces contaminants produced from stationary (industries, burning of fossil fuels, and stationary diesel engines) and mobile sources (automobile vehicles). The effects of particulate matter and soot on the environment and human health were also discussed. The disruption of photosynthesis in vegetation is due to the agglomeration of soot particles