Premium
Facile Formation of Nanostructured Manganese Oxide Films as High‐Performance Catalysts for the Oxygen Evolution Reaction
Author(s) -
Walter Carsten,
Menezes Prashanth W.,
Loos Stefan,
Dau Holger,
Driess Matthias
Publication year - 2018
Publication title -
chemsuschem
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.412
H-Index - 157
eISSN - 1864-564X
pISSN - 1864-5631
DOI - 10.1002/cssc.201800493
Subject(s) - oxidizing agent , catalysis , oxygen evolution , x ray photoelectron spectroscopy , materials science , manganese , chemical engineering , oxide , electrochemistry , electrolyte , water splitting , nanostructure , inorganic chemistry , nanotechnology , chemistry , electrode , organic chemistry , photocatalysis , engineering , metallurgy
The development of inexpensive, earth abundant, and bioinspired oxygen evolution electrocatalysts that are easily accessible and scalable is a principal requirement with regard to the feasibility of water splitting for large‐scale chemical energy storage. A unique, versatile, and scalable approach has been developed to fabricate manganese oxide films from single layers to multilayers with a controlled thickness and high reproducibility. The produced MnO x films are composed of small nanostructures that are assembled closely in the form of porous sponge‐like layers. The films were investigated for the electrochemical oxygen evolution reaction in alkaline media and demonstrate a remarkable activity as well as a superior stability of over 60 h. To elucidate the catalytically active species, as well as the striking structural characteristics, the films were further examined in depth by using SEM, TEM, and X‐ray photoelectron spectroscopy, as well as quasi in situ extended X‐ray absorption fine structure and X‐ray absorption near edge structure analysis. The MnO x catalyst films excel because of a favorably high fraction of Mn 3+ ions that are retained even after operation at oxidizing potentials. Upon exposure to oxidizing potentials in strongly alkaline aqueous electrolyte, the catalyst material maintains its structural integrity at the nanostructural, morphological, and atomic level.