Experimental and simulation of PEM water electrolyser with Pd/PN-CNPs electrodes for hydrogen evolution reaction: Performance assessment and validation

Water electrolysis using a proton exchange membrane (PEM) offers a sustainable solution for green hydrogen production from intermittent renewable energy sources. However, the utilization of costly electrode materials and cell components has resulted in expensive hydrogen production costs and limited its commercial applications. Furthermore, the management of gas-liquid flow and thermal distributions presents significant challenges in the operation of PEM water electrolysers. In this study, a COMSOL Multiphysics model was developed for a 25 cm2 single cell PEM water electrolyser with parallel flow field configurations to investigate its performance including operating principles, mechanisms, and ion transport properties. Subsequently, the model was validated with in-house experimental data at different operating conditions. Impressively, it effectively predicted the current-voltage polarization curves, demonstrating strong correlation with the experimental data. For a more rigorous comparison between experimental and numerical simulation, the normalized root mean square deviation was calculated for current-voltage polarization curves at various temperatures, ranging from 30 °C to 80 °C. The deviation was observed to be around 1.1% across all the temperatures, an acceptably low error value. In addition, the model was used to analyze the reactant flow and thermal distributions. This work can provide both experimental and simulation support for the selection and optimization of operating conditions, including flow fields in PEM water electrolysers.