Poly(3-thiophenemalonic acid) Modified NiFe Layered Double Hydroxide Electrocatalyst for Stable Seawater Oxidation at an Ampere-Scale Current Density

Seawater electrolysis shows potential for sustainable hydrogen production but faces challenges from the high concentration of Cl–, which leads to corrosion and performance degradation. In this study, we prepared a NiFe layered double hydroxide (NiFe LDH) nanoarray modified with poly(3-thiophenemalonic acid) (PTPA) on Ni foam (NiFe LDH@PTPA/NF) to enhance alkaline seawater oxidation (ASO). PTPA serves as a conductive and protective layer, improving electrical conductivity and repelling Cl– to increase stability. The electrode demonstrated stable operation at 1000 mA cm–2 with low overpotential for 600 h, generating minimal chlorine. In situ Raman spectroscopy confirmed that PTPA facilitates active site formation and provides Cl– protection, while inductively coupled plasma-optical emission spectrometry analysis indicated reduced Ni and Fe leaching. This study highlights the potential of conductive polymers to enhance ASO performance and durability.