Announcing the Final Examination of Wei Zhang for the degree of Doctor of Philosophy
In the pursuit of renewable and sustainable energy sources, this century presents humanity with an imperative driven by the crisis of conventional energy shortages and environmental pollution. Clean electrochemical energy storage and conversion technologies play a pivotal role in shaping the future landscape of power generation and energy utilization. However, the judicious design of the catalysts capable of efficiently and robustly driving electrochemical conversion remains a pressing challenge. In my dissertation, I addressed the critical challenges related to enhancing energy conversion efficiency in zinc-air batteries (ZABs) and electrocatalytic carbon dioxide reduction (CO2RR). These innovations show promise in utilizing renewable electricity to generate power and actively contribute to decarbonization efforts. The core focus of my dissertation revolves around the strategy of interface engineering for materials design and characterization. It is coupled with an in-depth mechanistic investigation of the structure-property relationship at the interface level. The construction of a strong metal-support oxide interaction (SMMOI) has been demonstrated in the PdNiMnO porous film and has shown promising results. This interaction significantly enhances the activity of oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) through electronic perturbation of Pd, reducing the reliance on precious metals and substantially improving the ZAB performance. On the other hand, my dissertation expands the decarbonization concept of electrocatalytic CO2RR towards value-added chemical production such as CO and formate. By designing bio-inspired tin oxide (SnOx) porous films through multiscale approaches of morphology engineering, surface chemistry, and phase transformation, the CO2RR Faradaic efficiency can be significantly improved. This is achieved by establishing a triple-phase interface and preserving the active phase through controlled pulsed electrochemical potentials during reactions. This innovative approach effectively addresses limitations associated with CO2 capture on the electrode and CO2 solubility issues in the electrolyte. The interface engineering strategies outlined in this dissertation illuminate the path toward next-generation catalyst designs that are highly efficient and tailored for sustainable and renewable energy applications
Committee in Charge:
Yang Yang, Chair, Materials Science and Engineering
James Fenton, Department of Materials Science and Engineering
Kevin Coffey, Department of Materials Science and Engineering
Yajie Dong, Department of Materials Science and Engineering
Abdelkader Kara, Department of Physics