Development of high-performance electrodes via surface and structural engineering of non-precious metal electrodes for water electrolysis

Abstract

This dissertation presents a comprehensive study on the development of high-performance electrodes for water electrolysis using non-precious metal materials through surface and structural engineering. Chapter 1 provides fundamental background on water electrolysis, covering the principles, advantages, and challenges of low-temperature electrolysis technologies such as alkaline water electrolysis (AWE) and anion exchange membrane water electrolysis (AEMWE). Particular emphasis is placed on the role of non-precious metal electrodes and the importance of engineering their surface and structure to enhance catalytic activity, durability, and system compatibility. In Chapter 2, a novel hydration-induced surface modification strategy is introduced, forming Ni(OH)2 and NiOOH layers on Ni foam that significantly enhance the oxygen evolution reaction (OER) activity in AWE. The modified surface exhibits improved charge transfer, increased ECSA, and excellent stability, while the hydrogen evolution reaction (HER) performance is hindered due to proton adsorption suppression—explained through experimental and DFT analyses. In Chapter 3, a structurally integrated electrode design is proposed for AEMWE, where catalytic and transport functions are unified into a single NiFe-based functionalized porous transport layer (f-PTL) via tape-casting and metallurgical sintering. The optimized NiFe-f-PTL demonstrates exceptional catalytic activity, efficient gas-liquid transport, superior membrane interface contact, and outstanding long-term durability exceeding 2,000 hours. These findings establish hydration and structural integration as effective and scalable strategies for advancing non-PGM electrodes, offering practical solutions for sustainable hydrogen production.