Experimental investigation and analysis of a novel photo-electrochemical hydrogen production cell with polymeric membrane photocathode

• Copper oxide photosensitizers on MPEA respond to light.
• The response depends on the type of oxide layer electrodeposited.
• Low compression on MPEA renders low current densities.

In this paper, a novel photo-electrochemical cell for hydrogen production is developed, tested and analyzed based on exergy method. As novelty, a membrane photo-electrode assembly (MPEA) is fabricated by electro-deposition of CuO/Cu2O semiconductor photo-catalysts on the cathode surface such that a polymeric membrane photocathode is formed. The reactor has a planar construction consisting of two half-cells separated by the MPEA with a total surface of 200 cm2. The MPEA is pre-doped with platinum electro-catalyst both at anode and cathode. Both dark-exposure and light-exposure tests using voltammetry clearly demonstrate the beneficial effect of the photocathode which enhances the rate of hydrogen production by increasing the current density and lowering the bias voltage. In addition, hydrogen evolution measurements confirm the cell functionality and allowed for efficiency determination. The experimental work is also used to validate a simple phenomenological model based on an electric equivalent diagram of the photo-electrochemical process which further is used to quantify the various kinds of irreversibility by evaluation of the exergy destructions.