Particle size-controlled synthesis of high-performance MnCo-based materials for alkaline OER at fluctuating potentials. Issue 22 (8th October 2021)

• Record Type: Journal Article
• Authors: Broicher, Cornelia; Klingenhof, Malte; Frisch, Marvin; Dresp, Sören; Kubo, Nikolas Mao; Artz, Jens; Radnik, Jörg; Palkovits, Stefan; Beine, Anna Katharina; Strasser, Peter; Palkovits, Regina
• Is Part Of: Catalysis science & technology. Volume 11:Issue 22(2021)
• Page Start: 7278
• Page End: 7286
• Publication Date: 2021-10-08
• Subjects: Catalysis -- Periodicals; 541.395
• DOI: 10.1039/d1cy00905b
• Languages: English
• ISSNs: 2044-4753

Abstract

Abstract : Mn and Co containing nanocubes were produced by hydrothermal synthesis. The materials consist of metal spinels and carbonates, where spinels ensure high activity and carbonates contribute to high stability in the oxygen evolution reaction. Abstract : For the large-scale generation of hydrogen via water electrolysis the design of long term stable and active catalysts for the oxygen evolution reaction (OER) remains a key challenge. Most catalysts suffer from severe structural corrosion that becomes even more pronounced at fluctuating potentials. Herein, MnCo based cubic particles were prepared via a hydrothermal approach, in which the edge length of the micron-sized particles can be controlled by changing the pH value of the precursor solution. The cubes are composed of varying amounts of MnCo2 O4, CoCO3 and a mixed (Mn/Co)CO3 phase. Structure–activity relationships were deduced revealing a volcano-type behavior for the intrinsic OER activity and fraction of spinel oxide phase. A low overpotential of 0.37 V at 10 mA cm −2 and a stability of more than 25 h was achieved in 1.0 M KOH using a rotating disc electrode (RDE) setup. The best performing catalyst material was successfully tested under dynamic process conditions for 9.5 h and shows a superior catalytic activity as anode for the overall water splitting in an electrolyser setup in 1.0 M KOH at 333 K compared to a reference NiCo-spinel catalyst.