Ethylene electrosynthesis from low-concentrated acetylene via concave-surface enriched reactant and improved mass transfer.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 39003284.
- Also identified by DOI 10.1038/s41467-024-50335-8 and PMC identifier 11246534.
- 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
Electrocatalytic semihydrogenation of acetylene (C<sub>2</sub>H<sub>2</sub>) provides a facile and petroleum-independent strategy for ethylene (C<sub>2</sub>H<sub>4</sub>) production. However, the reliance on the preseparation and concentration of raw coal-derived C<sub>2</sub>H<sub>2</sub> hinders its economic potential. Here, a concave surface is predicted to be beneficial for enriching C<sub>2</sub>H<sub>2</sub> and optimizing its mass transfer kinetics, thus leading to a high partial pressure of C<sub>2</sub>H<sub>2</sub> around active sites for the direct conversion of raw coal-derived C<sub>2</sub>H<sub>2</sub>. Then, a porous concave carbon-supported Cu nanoparticle (Cu-PCC) electrode is designed to enrich the C<sub>2</sub>H<sub>2</sub> gas around the Cu sites. As a result, the as-prepared electrode enables a 91.7% C<sub>2</sub>H<sub>4</sub> Faradaic efficiency and a 56.31% C<sub>2</sub>H<sub>2</sub> single-pass conversion under a simulated raw coal-derived C<sub>2</sub>H<sub>2</sub> atmosphere (~15%) at a partial current density of 0.42 A cm<sup>-2</sup>, greatly outperforming its counterpart without concave surface supports. The strengthened intermolecular π conjugation caused by the increased C<sub>2</sub>H<sub>2</sub> coverage is revealed to result in the delocalization of π electrons in C<sub>2</sub>H<sub>2</sub>, consequently promoting C<sub>2</sub>H<sub>2</sub> activation, suppressing hydrogen evolution competition and enhancing C<sub>2</sub>H<sub>4</sub> selectivity.