High Pressure (6 MPa) H-Type Electrochemical Cell with Single Chamber, CHPHTECSC

A high-pressure electrochemical cell with a single chamber (often referred to as a "monoblock" or "single-compartment autoclave cell") is designed for reactions where the separation of the anode and cathode products is either unnecessary or managed through the chemistry itself. These cells are preferred for studies involving gas solubility (like CO2 reduction), hydrothermal electrochemistry, or corrosion testing in extreme environments. Because there is no membrane or diaphragm, the cell is mechanically simpler and can often reach much higher pressures than dual-chamber designs.

In this setup, both the working electrode (WE), counter electrode (CE), and reference electrode (RE) are immersed in the same electrolyte volume within a single pressurized vessel. (1) Pressure Vessel: Typically a thick-walled cylinder made of 316 Stainless Steel, Hastelloy C276 (for superior corrosion resistance), or Titanium. (2) Internal Liner: Often lined with PTFE (Teflon) or PEEK to prevent the metal walls of the vessel from participating in the electrochemical reaction or short-circuiting the electrodes. (3) Electrode Feedthroughs: High-pressure "glands" (Conax-style) that allow electrical wires to pass from the pressurized interior to the external potentiostat without leaking.

References:

1. H. Ohnaru, et al., High pressure H-type electrochemical cell enabling gas collection: application to CO₂ electrolysis, High Pressure Research, 2026, DOI: 10.1080/08957959.2026.2624012. 

2. B. Endrődi, et al. Multilayer Electrolyzer Stack Converts Carbon Dioxide to Gas Products at High Pressure with High Efficiency, ACS Energy Lett. 2019, 4, 7, 1770–1777.