NiMo electrocatalysts from a deep eutectic solvent for the hydrogen evolution reaction

Author(s):Show less -

Sousa, Natalia G. ; Bezerra, Lucas L. ; Gomes, Kauan L. ; Feitosa, Filipe X. ; Sant'Ana, Hosiberto B. de ; Mascaro, Lucia H. ; Schwarzacher, Walther ; de Lima-Neto, Pedro ; Monteiro, Norberto K. V. ; Casciano, Paulo N. S. ; Correia, Adriana N.

• Document type: Journal article
• Source: INTERNATIONAL JOURNAL OF HYDROGEN ENERGY; v. 142, p. 9-pg., 2025-06-27.

Abstract

Here we report the influence of temperature on the electrodeposition of NiMo in a mixture of choline chloride (ChCl) and ethylene glycol (EG) with molar ratio 1:2 (ethaline) on Cu substrate and its consequences for the hydrogen evolution reaction (HER). Potentiostatic deposition of Ni and NiMo at 298 K resulted in thin films; at 343 K, the morphology was cauliflower-like for Ni and NiMo, with 4 % Mo content. The electrocatalytic performance of the water-splitting coatings was evaluated by linear sweep voltammetry (LSV) in 1 M KOH. The electrocatalytic tests allowed us to establish the performance sequence of the deposits: Ni94Mo6>Ni98Mo2>Ni-343K > Ni-298K. Electrochemical impedance spectroscopy (EIS) results showed that the NiMo coatings had significantly lower charge transfer resistance (R-CT) values than the Ni-only coatings despite containing only a small percentage of Mo. Computational simulations indicated that the Ni96Mo4 surface has the highest catalytic performance due to the near-zero Gibbs energy of water adsorption relative to Ni-100. (AU)

• FAPESP's process: 13/07296-2 - CDMF - Center for the Development of Functional Materials
• Grantee: Elson Longo da Silva
• Support Opportunities: Research Grants - Research, Innovation and Dissemination Centers - RIDC
• FAPESP's process: 17/11986-5 - Generation and storage of New Energy: bringing technological development for the country
• Grantee: Ana Flávia Nogueira
• Support Opportunities: Research Grants - Research Centers in Engineering Program