Iron and Manganese Containing Multi‐Walled Carbon Nanotubes as Electrocatalysts for the Oxygen Evolution Reaction ‐ Unravelling Influences on Activity and Stability. Issue 21 (24th September 2020)

• Record Type: Journal Article
• Authors: Broicher, Cornelia; Zeng, Feng; Pfänder, Norbert; Frisch, Marvin; Bisswanger, Timo; Radnik, Jörg; Stockmann, Jörg Manfred; Palkovits, Stefan; Beine, Anna Katharina; Palkovits, Regina
• Is Part Of: ChemCatChem. Volume 12:Issue 21(2020)
• Page Start: 5378
• Page End: 5384
• Publication Date: 2020-09-24
• Subjects: Catalysis -- Periodicals; 541.39505
• DOI: 10.1002/cctc.202000944
• Languages: English
• ISSNs: 1867-3880

Abstract

Abstract: Hydrogen economy is a central aspect of future energy supply, as hydrogen can be used as energy storage and fuel. In order to make water electrolysis efficient, the limiting oxygen evolution reaction (OER) needs to be optimized. Therefore, C‐based composite materials containing earth‐abundant Fe and Mn were synthesized, characterized and tested in the OER. For pyrolysis temperatures above 700 °C N‐rich multi‐walled carbon nanotubes (MWCNT) are obtained. Inside the tubes Fe3 C particles are formed, Fe and Mn oxides are incorporated in the carbon matrix and metal spinel nanoparticles cover the outer surface. The best catalyst prepared at 800 °C achieves a low overpotential of 389 mV (at 10 mA/cm 2 ) and high stability (22.6 h). From electrochemical measurements and characterization it can be concluded that the high activity is mainly provided by MWCNT, Fe3 C and the metal oxides in the conductive carbon matrix. The metal spinel nanoparticles in contrast protect the MWCNT from oxidation and thereby contribute to the high stability. Abstract : Electrocatalysis : Composite materials of iron, manganese and N‐rich carbon were synthesized, characterized and tested in the oxygen evolution reaction (OER). The best catalyst shows a low overpotential of 389 mV (at 10 mA/cm 2 ) resulting from Fe3 C and the N‐rich, Fe and Mn oxides containing MWCNT. The high stability (22.6 h) was assigned to the presence of Mn3 O4 and Fe3 O4 on the outer surface of the tubes.