Direct electrodeposition of <scp>Ni‐Co‐S</scp> on carbon paper as an efficient cathode for anion exchange membrane water electrolysers
Wenwu Guo, Junhyeong Kim, Hyunki Kim, Sang Hyun Ahn
Abstract
The development of an efficient water electrolyser is essential for sustainable hydrogen production; however, its application remains limited by the insufficient performance of the electrode. Herein, we report a rapid, simple, and cost-effective fabrication of an Ni-Co-S cathode for the hydrogen evolution reaction (HER), which is directly usable for an anion exchange membrane water electrolyser (AEMWE). The Ni-Co-S electrocatalysts are prepared on a carbon paper (CP) substrate by a one-step electrodeposition method by controlling deposition parameters such as the deposition potential, time, and electrolyte composition. The optimized Ni-Co-S/CP electrode demonstrates a high HER activity with an overpotential of 91 mV at −10 mA/cm2 in 1.0 M KOH. An AEMWE single cell employing the Ni-Co-S/CP cathode coupled with a commercial IrO2/CP anode exhibits a current density of 1.7 A/cm2 at 2.4 Vcell, which is higher than that of an AEMWE single cell with a commercial Pt/C/CP cathode; this is attributable to the enhancement of the electron and reactant/product transfer via appropriate cathode design.