A novel catalyst layer with hydrophilic–hydrophobic meshwork and pore structure for solid polymer electrolyte water electrolysis

Abstract

A hydrophilic–hydrophobic catalyst coated membrane (CCM) for solid polymer electrolyte (SPE) water electrolysis was prepared to decrease oxygen transmission resistance by adding PTFE into the conventional hydrophilic catalyst layer (CL). The property and performance of the modified CCM were analyzed and evaluated by scanning electron microscopy (SEM), energy disperse spectroscopy (EDS), electrochemistry impedance spectroscopy (EIS), linear sweep voltammetry (LSV) and I–V curves. The SEM and EDS revealed that a hydrophilic–hydrophobic cross-linked structure was fabricated via Nafion and PTFE, and catalyst dispersed well among the above structure. The electrochemical tests showed that terminal voltage was 1.68 V at 80 °C and 2 A cm − 2 , which was a remarkable improvement compared with the conventional hydrophilic CL. The key factor responsible for the improved performance is the optimization of electrode structure.