Keywords and Phrases
Electrocatalysts; Hydrogen Evolution Reaction; Metal Chalcogenides; Oxygen Evolution Reaction; Oxygen Reduction Reaction; Water Oxidation
”The rising demand for energy security and reducing fossil fuel dependence has prompted researchers to search for a clean, sustainable, and efficient energy generation system with low environmental impact. Water electrolysis has been identified as one of the most important processes satisfying the above needs to generate hydrogen as a clean fuel. Two half-cell reactions of oxygen evolution reaction (OER) at the anode and hydrogen evolution reaction (HER) at the cathode comprise the main process of water electrolysis. However, the oxygen evolution reaction is the most crucial step for efficient water splitting. Traditionally, metal oxides have been utilized as catalysts to enhance OER. Recent developments however have shown that transition metal chalcogenides exhibit better OER electrocatalytic activity surpassing state-of-the-art precious oxides.
In this research, the design principle of these electrocatalysts was explored further and the highly efficient OER catalytic activity of tellurides with various transition metals including Ni and Co was demonstrated. Interestingly it was observed that telluride-based electrocatalysts exhibited some of the lowest overpotentials reported to date along with high current density, surpassing those reported with analogous oxides and selenides. This research thus validated the primary hypothesis that decreasing anion electronegativity is instrumental in improving electrocatalytic activity, by tuning electrochemical response around the active transition metal site. This project also focused on understanding the active surface composition of chalcogenide electrocatalysts by measuring the catalytic activity of tailor-made surfaces and comparing it with constructed surface models. The effect of nanostructuring on the electrocatalytic performance was also investigated”--Abstract, page iv.
Winiarz, Jeffrey G.
Ph. D. in Chemistry
Missouri University of Science and Technology
Journal article titles appearing in thesis/dissertation
- Nickel telluride as a bifunctional electrocatalyst for efficient water splitting in alkaline medium
- Intrinsic Activity of Trifunctional Electrocatalyst: Cobalt Telluride in Alkaline Medium
- Understanding Surface Structural Evolution of Nickel Chalcogenide Electrocatalysts for Water Oxidation
- Magnetic Multifunctional Nanostructures as High-efficiency Catalysts for Oxygen Evolution Reactions
- Synthesis and characterization of a series of nickel selenides for high efficient water oxidation catalysis
xvi, 275 pages
© 2021 Sammu Handi Umanga Iroshini De Silva, All rights reserved.
Dissertation - Open Access
De Silva, Umanga, "Designing transition metal chalcogenides electrocatalyst surfaces for high-efficiency water oxidation" (2021). Doctoral Dissertations. 3072.