Novel nanostructured electrocatalysts for hydrogen evolution reaction in neutral and weak acidic solutions

Microbial electrolysis cells (MECs) provide an innovative bioelectrochemical approach for hydrogen production using microorganisms as biocatalysts. The development of cost-effective cathodes for near-neutral pH and ambient temperature conditions is the most critical challenge for the practical application of MEC technology. In this study, the electrocatalytic properties of electrodeposited onto carbon felt NiFe-, NiFeP- and NiFeCoP-nanostructures towards HER in neutral and weak acidic solutions were investigated. The voltage needed to initiate hydrogen production and the current production rates were estimated from obtained linear voltammograms. The developed composite materials possess much higher catalytic activity than bare carbon felt. The highest current production rate corresponding to 1.7 ± 0.1 m3H2/day/m2 was achieved with NiFeCoP/carbon felt electrodes. In addition, the applied modifications result in improvement of the corrosion resistance. The obtained results demonstrate that Ni-based nanomodified materials are promising electrocatalysts for HER in near-neutral electrolytes and could be applied as cathodes in MECs.

► Electrodeposition of NiFe-, NiFeP-, NiFeCoP-island-nanostructures on carbon felt. ► Higher corrosion stability of nanomodified materials in near-neutral solutions. ► Electrocatalytic activity towards HER increasing in order NiFe < NiFeP < NiFeCoP. ► Hydrogen production rate of 1.7 ± 0.1 m3H2/day/m2 with NiFeCoP/carbon felt electrodes. ► Potential application of novel materials as cathodes in microbial electrolysis cells.