Electrodeposited nickel phosphide supported by copper foam for proton exchange membrane water electrolyzer

The development of high-performance and low-cost electrodes is essential for hydrogen production using a proton exchange membrane water electrolyzer (PEMWE). Herein, we report an electrochemical method for the fabrication of a Ni-P based cathode for a PEMWE single cell. A porous copper foam (CF) is fabricated on carbon paper (CP) by two-step electrodeposition to obtain a large number of active sites for Ni-P formation. The high conductivity of the Cu metallic support is expected to reduce the charge transfer resistance. After the Ni-P electrodeposition on CF, an anodic leaching process is conducted for the selective dissolution of the excess Ni metal formed during the electro-deposition, thus enabling the modification of the electronic structure of the catalyst. The electrode optimized in half-cell tests is used as the cathode for a PEMWE single cell. The PEMWE cells exhibit a current density of 0.67 A/cm² at 2.0 V_cell which is higher than or comparable to the performance previously reported in the literature.