Application and Analysis of a Salt Bridge Reference Electrode Setup for PEM Water Electrolysis: Towards an Extended Voltage Loss Break Down

Abstract

Information on proton exchange membrane water electrolysis performance is often obtained from full cell measurements. The level of detail of this information is, however, comparably low. This contribution analyzes kinetic parameters for anode and cathode reactions separately as a step towards an extended loss breakdown through a salt bridge reference electrode. The reference electrode setup is shown in detail, and qualitative measurements are discussed. Oxygen evolution reaction and hydrogen evolution reaction Tafel slopes and exchange current densities for both reactions are reported. An outlook on future use cases for the salt bridge reference electrode is given and supported by measurement data.

Adaptation of a PEMFC Reference Electrode to PEMWE: Possibilities and Limitations

“…HER exchange current density from linear fitting resulted in 186.9⋅10 −3 A cm −2 . 7 Generally, the measured Tafel slope and exchange current density fall in the same range. The present work resulted in a slight shift towards lower b and larger i 0 for the OER.…”

“…The determined kinetic parameters are in good agreement with recently published values, where a different RE was used. 7 There, the Tafel slopes for OER were measured between 49-51 mV dec −1 . OER exchange current densities were measured between 7.03⋅10 −8 to 1.0⋅10 −7 A cm −2 .…”

“…12 A general equation for the cell potential can be found in Ref. 7. The cell voltage can be further decomposed into the anode and cathode contributions (Eq.…”

“…[4][5][6] These REs require adjustments to the materials, for example, an ionomer treatment of the porous transport layer (PTL) in case of the salt bridge or specific CCM preparation for the other two types. 7 This work focuses on DHEs since they require minimal intervention in the cell material. Past approaches from FC research will be reviewed, followed by existing approaches for WE.…”

Electrochemical Hydrogen Evolution Reaction Evaluation of CoNi(Cr/V) Medium-Entropy Alloys in an Acidic Environment

“…The Ag/AgCl reference electrode was calibrated against the Pt electrode before and after the LSV experiment to ensure that the reference potential did not drift, and the calibrated voltage was 0.273 V versus the Pt electrode (Figure S1). To avoid any voltage drift of the reference electrode, a salt bridge was employed by following recent literature . All of the potentials were converted to reference hydrogen electrodes using the Nernst equation ( E RHE = E Ag/AgCl + 0.273 V).…”