Tailoring NiFeS microstructure through electrodeposition for high-performance anion exchange membrane water electrolysis

Journal of Power Sources, vol. 657, pp. 238128

Abstract

Sustainable hydrogen production from anion exchange membrane (AEM) water electrolysis is an economically efficient alternative to proton exchange membrane (PEM) technology. However, conventional ionomer-based spray-coated electrodes suffer from poor conductivity and low utilization of active sites. These are primarily due to the agglomeration of ionomers with the catalyst, leading to uneven dispersion and significant catalyst active surface area blockage. A self-supported, ionomer-free NiFeS OER catalyst, synthesized via direct electrodeposition on a nickel fiber porous transport layer, is introduced here to address these limitations. The optimized NiFeS catalyst required only 300 mV as overpotential to accomplish 100 mA cm −2 , exhibiting superior charge transfer kinetics, as evidenced by a low Tafel slope of 84 mV dec −1 . The catalyst also had a significantly larger electrochemically active surface area (ECSA) than its monometallic counterparts. NiFeS-based electrolyzer in a practical AEMWE setup achieved an outstanding current density of 2.6 A cm −2 at 2.0 V, showing minimal voltage degradation over 100 h of operation at 1 A cm −2 and 60 °C, underscoring the applicability and durability of this catalyst for efficient hydrogen production.

Authors 7

1. Marina Medina

   Universidade Federal de São Carlos

   Affiliation as printed

   Universidade Federal de São Carlos, Departamento de Química, Rod. Washington Luiz, Km 235, 13565-905, São Carlos, SP, Brazil

2. Anelisse Brunca da Silva

   Universidade Federal de São Carlos

   Affiliation as printed

   Universidade Federal de São Carlos, Departamento de Química, Rod. Washington Luiz, Km 235, 13565-905, São Carlos, SP, Brazil

3. Lu Xia Aachen Faculty of Mechanical Engineering

   Forschungszentrum Jülich · RWTH Aachen University

   Affiliation as printed

   Faculty of Mechanical Engineering, RWTH Aachen University, 52062, Aachen, Germany

   Institute of Energy Technologies, Electrochemical Process Engineering (IET-4), Forschungszentrum Jülich GmbH, 52425, Jülich, Germany

4. Wulyu Jiang Aachen Faculty of Mechanical Engineering

   Forschungszentrum Jülich · RWTH Aachen University

   Affiliation as printed

   Faculty of Mechanical Engineering, RWTH Aachen University, 52062, Aachen, Germany

   Institute of Energy Technologies, Electrochemical Process Engineering (IET-4), Forschungszentrum Jülich GmbH, 52425, Jülich, Germany

5. Andreas Glüsen

   Forschungszentrum Jülich

   Affiliation as printed

   Institute of Energy Technologies, Electrochemical Process Engineering (IET-4), Forschungszentrum Jülich GmbH, 52425, Jülich, Germany

6. Cauê Ribeiro

   Brazilian Agricultural Research Corporation · Embrapa Instrumentação

   Affiliation as printed

   National Nanotechnology Laboratory for Agribusiness (LNNA), EMBRAPA Instrumentação, CP, São Carlos, SP, 13560-970, Brazil

7. Lucia Helena Mascaro corresponding

   Universidade Federal de São Carlos

   Affiliation as printed

   Universidade Federal de São Carlos, Departamento de Química, Rod. Washington Luiz, Km 235, 13565-905, São Carlos, SP, Brazil