Chemical and Biological Engineering ETDs

Publication Date

Spring 4-13-2018

Abstract

Proton exchange membrane fuel cells offer a cost-effective, environmentally friendly, and sustainable alternative to petroleum-based power sources to the transportation sector. However, slow electrochemical reactions at the cathode of these fuel cell prevent the technology from being competitive. Iron-nitrogen-carbon based catalysts have emerged as a viable answer to this problem, yet further progress is needed to improve their performance beyond that of current state-of-the-art platinum-based catalysts, which are economically and geopolitically impractical to be a final solution. Currently, a two-step high temperature pyrolysis method has proven a promising way to synthesize iron-nitrogen-carbon catalysts for optimized performance, but there is a lack of general understanding as to why these techniques are so efficacious. In this study, iron-nitrogen-carbon catalysts are synthesized with varying second pyrolysis durations and analyzed in regard to their chemistry, morphology, and performance through x-ray photoelectron spectroscopy, scanning electron microscopy, and rotating ring disk electrode techniques to attempt to find trends between high performance and the occurrence of specific chemical compositions or morphologies. It is reported that relative increases in pyridinic nitrogen and nitrogen coordinated to metal contents coincide with improved performance and that longer pyrolysis times promote heterogeneity and small scale porosity in these materials.

Keywords

fuel cell, non-PGM, ORR, catalyst, synthesis effects

Document Type

Thesis

Language

English

Degree Name

Chemical Engineering

Level of Degree

Masters

Department Name

Chemical and Biological Engineering

First Committee Member (Chair)

Plamen Atanassov

Second Committee Member

Kateryna Artyushkova

Third Committee Member

Fernando Garzon

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