Absolutely Sealed Gas-Tight Replaceable Membrane H-Cell

What it is and how it works The Absolutely Sealed Gas-Tight Replaceable Membrane H-Cell is a two-compartment electrochemical reactor designed for experiments that require (i) separation of anode and cathode products and (ii) controlled headspace conditions . The compartments are separated by an ion-exchange membrane (AEM/CEM), which allows ionic conduction while reducing molecular crossover. This improves selectivity and interpretability in electrolysis and electrocatalysis studies, especially when products are sampled for analysis. Standard construction features Cell body: chemically resistant borosilicate glass for aqueous and many non-aqueous electrolytes Replaceable membrane clamp: compression sealing for repeatable assembly and rapid membrane swaps Gas-tight electrode ports: PTFE cap/cover with O-ring or compression sealing to minimise oxygen ingress and solvent evaporation Two-chamber geometry: supports independent electrolyte compositions (e.g., different pH, different supporting salts, different catalysts) Optional configurations & accessories (application-driven) Valve / gas-handling ports: for purge/vent, controlled gas feed (e.g., CO₂), headspace sampling, and pressure equalisation Optical window (e.g., quartz): for photoelectrochemistry or spectroelectrochemistry where optical access is required Jacketed temperature-control version: for circulating thermostated fluid to stabilise kinetics, solubility, and gas–liquid equilibria Electrode fixtures/adaptors: to suit planar electrodes, gas-diffusion electrodes, or specific reference electrode formats Gas-tight (absolutely sealed) vs standard screw-cap H-cell: which to choose Choose gas-tight when you need: Quantitative gas experiments (CO₂RR/HER/OER) where leaks or air ingress distort faradaic efficiency and gas composition Stable electrolyte concentration during long runs (reduced evaporation and CO₂ loss) Air-sensitive chemistries (oxygen/moisture-sensitive catalysts, non-aqueous electrolytes, metal plating/stripping) Reproducible headspace control for mechanistic comparisons across conditions Choose a screw-cap H-cell when: Running routine aqueous screening where minor air exchange is acceptable You are not quantifying gas products and short experiments minimise evaporation impacts You prioritise fast setup and lower complexity for early-stage catalyst benchmarking or teaching labs Typical applications and instrumentation pairing Common uses include CO₂ reduction, selective electrolysis with product separation, membrane screening, corrosion inhibitor studies, and half-cell investigations. Pair with a suitable potentiostat/galvanostat, reference electrodes, and (when needed) gas handling and downstream analytics. ScienceGears can help specify membrane type, sealing consumables, and compatible electrochemical instrumentation and accessories.