• • Glycine-intercalated NiFe-LDH achieves an overpotential of 240 mV at 10 mA cm−2 in 1.0 M KOH, a 40 mV improvement over pristine NiFe-LDH (280 mV), directly lowering the energy input required for hydrogen production.
• • The Tafel slope is reduced to 38 mV dec−1 from 52 mV dec−1, indicating faster reaction kinetics and more favorable charge transfer, which is critical for high-current-density industrial electrolyzers.
• • The electrochemically active surface area increases by 2.3-fold, and charge transfer resistance drops from 12.5 Ω to 4.8 Ω, enhancing catalytic site accessibility and electron transport, thereby improving overall electrode efficiency.
• • Long-term stability is demonstrated with 95% activity retention after 24 h of continuous operation at 10 mA cm−2, addressing durability concerns for practical water splitting applications.