Reference electrode (Hydrogen) – Hydroflex

The BioLogic Hydroflex is a commercially available reversible hydrogen electrode (RHE) that provides a hydrogen-based reference potential directly traceable to the reversible hydrogen electrode scale. Unlike conventional reference electrodes (Ag/AgCl, SCE, Hg/HgO) that require a pH-dependent potential correction to convert the measured potential to the RHE scale, the Hydroflex provides a potential that is already on the RHE scale by design — it maintains a hydrogen electrode equilibrium in the cell solution itself.

This makes the Hydroflex the ideal reference electrode for electrocatalysis research, particularly for measurements of the hydrogen evolution reaction (HER), oxygen evolution reaction (OER), oxygen reduction reaction (ORR), and other electrochemical energy conversion reactions where potentials are conventionally reported on the RHE scale. Using a true RHE reference eliminates the pH-conversion uncertainty that arises when converting potentials from Ag/AgCl or SCE references, which is especially significant in alkaline electrolytes where pH can vary or be uncertain.

The Hydroflex generates hydrogen gas in situ by electrolysis of the cell solution to maintain the H2/H+ equilibrium at the reference element, making it work correctly at any pH from strongly acidic to strongly alkaline. This universal applicability across the full pH range — 0 to 14 — without recalibration is a major practical advantage for researchers working with different electrolytes. NewRoad provides the BioLogic Hydroflex in Israel for electrochemistry and electrocatalysis laboratories focused on energy conversion and storage applications.