Carbonate oxidation via dehydrogenation on LiNi0.8Co0.1Mn0.1O2 at voltages as low as 3.8 VLi was revealed by in situ FT-IR measurements.

The kinetics of aqueous outer-sphere electron-transfer (ET) reactions are determined in large part by noncovalent electrostatic interactions that originate from the surrounding electrolyte solution. In this work, we examine the role of spectator cations in modifying the rate of heterogeneous ET for an [Fe­(CN)6]3–/[Fe­(CN)6]4– redox pair. We combine the results of electrochemical measurement, in situ surface-enhanced infrared absorption spectroscopy (SEIRAS), classical molecular dynamics simulation, and theoretical modeling to demonstrate how changing the identity of the spectator cation species over a series that includes Li+, Na+, K+, Rb+ to Cs+ influences the solvation properties and ET kinetics of the redox species. By analyzing the results in the context of the Marcus–Hush–Chidsey (MHC) theory, we find that the solvent reorganization energy increases systematically as the cationic radius decreases. The trend can be attributed to cation-dependent coordination environments of the redox species, whereby more cations of less charge density such as Cs+ than Li+ are present in the redox solvation shell in bulk and at the electrified interface, promoting weaker hydrogen bonds and lowering the effective interfacial static dielectric constant. We discuss the implications of these findings for enabling the tunability of reaction thermodynamics and rates in electrochemical processes.

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To my supervisor, Prof. Yeow. Thank you for giving me the opportunity to work in AMNDL. Thank you for supporting all the equipment/materials, and facility accesses. I know how expensive they are and without you, I would not have been able to execute my ideas and finish the projects. To my committees, Prof. Huissoon, Prof. Nieva and Prof. Stashuk, Thank you for all the comments and suggestions on my project. Additionally, I would say thank you to Prof. Huissoon. You gave me the to come to study in Waterloo and I will never forget the time I received your email where you asked me to come to Canada. To Prof. Cretu, thank you for agreeing to be the external committee and travelling to Waterloo for my defence. The CMUTs in this thesis were fabricated in G2N and TNFC. I would say thank Richard,

Careful rheological design and electrochemical optimization of conductive ZnO and Ni(OH)2 active semi-solid flowable electrodes is essential to achieve a high-energy and high-power Zn–Ni flow battery.