Dual properties of a hydrogen oxidation Ni-catalyst entrapped within a polymer promote self-defense against oxygen.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 29491416.
- Also identified by DOI 10.1038/s41467-018-03011-7 and PMC identifier 5830441.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
The Ni(P<sub>2</sub>N<sub>2</sub>)<sub>2</sub> catalysts are among the most efficient non-noble-metal based molecular catalysts for H<sub>2</sub> cycling. However, these catalysts are O<sub>2</sub> sensitive and lack long term stability under operating conditions. Here, we show that in a redox silent polymer matrix the catalyst is dispersed into two functionally different reaction layers. Close to the electrode surface is the "active" layer where the catalyst oxidizes H<sub>2</sub> and exchanges electrons with the electrode generating a current. At the outer film boundary, insulation of the catalyst from the electrode forms a "protection" layer in which H<sub>2</sub> is used by the catalyst to convert O<sub>2</sub> to H<sub>2</sub>O, thereby providing the "active" layer with a barrier against O<sub>2</sub>. This simple but efficient polymer-based electrode design solves one of the biggest limitations of these otherwise very efficient catalysts enhancing its stability for catalytic H<sub>2</sub> oxidation as well as O<sub>2</sub> tolerance.