Highly selective oxygen reduction to hydrogen peroxide on transition metal single atom coordination.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 31488826.
- Also identified by DOI 10.1038/s41467-019-11992-2 and PMC identifier 6728328.
- 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
Shifting electrochemical oxygen reduction towards 2e<sup>-</sup> pathway to hydrogen peroxide (H<sub>2</sub>O<sub>2</sub>), instead of the traditional 4e<sup>-</sup> to water, becomes increasingly important as a green method for H<sub>2</sub>O<sub>2</sub> generation. Here, through a flexible control of oxygen reduction pathways on different transition metal single atom coordination in carbon nanotube, we discovered Fe-C-O as an efficient H<sub>2</sub>O<sub>2</sub> catalyst, with an unprecedented onset of 0.822 V versus reversible hydrogen electrode in 0.1 M KOH to deliver 0.1 mA cm<sup>-2</sup> H<sub>2</sub>O<sub>2</sub> current, and a high H<sub>2</sub>O<sub>2</sub> selectivity of above 95% in both alkaline and neutral pH. A wide range tuning of 2e<sup>-</sup>/4e<sup>-</sup> ORR pathways was achieved via different metal centers or neighboring metalloid coordination. Density functional theory calculations indicate that the Fe-C-O motifs, in a sharp contrast to the well-known Fe-C-N for 4e<sup>-</sup>, are responsible for the H<sub>2</sub>O<sub>2</sub> pathway. This iron single atom catalyst demonstrated an effective water disinfection as a representative application.