Committee Members Information

• Ph.D. Advisor: Professor Xu Lu (KAUST, Chemistry)
• External Examiner: Professor Yifei Wang (Harbin Institute of Technology)
• Committee Chair: Professor Yun Hau Ng (KAUST, Chemical Engineering)
• 4th Committee Member: Professor Cafer T. Yavuz (KASUT, Chemistry)

Abstract

Electrochemical carbon dioxide reduction offers a promising route for converting CO2 into valuable chemicals, yet its practical implementation remains limited by mass-transfer constraints, product selectivity, and operational stability. This dissertation investigates how elevated pressure, dynamic catalyst surfaces, and dynamic interfacial microenvironments regulate CO2 electroreduction.

First, atomically mobile liquid metals are shown to form highly adaptive surfaces that dynamically accommodate adsorbed intermediates, thereby accelerating CO2-to-formate conversion. Second, a quantitative framework integrating electrochemical analysis, and microkinetic modeling distinguishes the effects of pressure on mass transport and reaction kinetics. Increasing the pressure from 1 to 20 bar substantially improves reaction performance, while further enhancement plateaus between 20 and 30 bar as kinetic control becomes dominant. Finally, pressure-modulated pulsed electrolysis in membrane electrode assemblies dynamically steers product selectivity: ambient-pressure pulsing favors ethanol formation, whereas elevated pressure shifts the reaction pathway toward CO. Optimized pulse conditions enable stable operation for over 24 hours at industrially relevant current densities. Together, these findings advance the mechanistic understanding of CO₂ electroreduction