Atomically dispersed Pt-N<sub>4</sub> sites as efficient and selective electrocatalysts for the chlorine evolution reaction.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 31964881.
- Also identified by DOI 10.1038/s41467-019-14272-1 and PMC identifier 6972710.
- 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
Chlorine evolution reaction (CER) is a critical anode reaction in chlor-alkali electrolysis. Although precious metal-based mixed metal oxides (MMOs) have been widely used as CER catalysts, they suffer from the concomitant generation of oxygen during the CER. Herein, we demonstrate that atomically dispersed Pt-N<sub>4</sub> sites doped on a carbon nanotube (Pt<sub>1</sub>/CNT) can catalyse the CER with excellent activity and selectivity. The Pt<sub>1</sub>/CNT catalyst shows superior CER activity to a Pt nanoparticle-based catalyst and a commercial Ru/Ir-based MMO catalyst. Notably, Pt<sub>1</sub>/CNT exhibits near 100% CER selectivity even in acidic media, with low Cl<sup>-</sup> concentrations (0.1 M), as well as in neutral media, whereas the MMO catalyst shows substantially lower CER selectivity. In situ electrochemical X-ray absorption spectroscopy reveals the direct adsorption of Cl<sup>-</sup> on Pt-N<sub>4</sub> sites during the CER. Density functional theory calculations suggest the PtN<sub>4</sub>C<sub>12</sub> site as the most plausible active site structure for the CER.