The effect of edge carbon of carbon nanotubes on the electrocatalytic performance of oxygen reduction reaction

•The carbon nanotubes (CNTs) with the different ratios of edge carbons are designed.•The ORR activity of CNTs can be improved by exposing more edge carbon atoms.•The dependence of ORR activity on the ratios of edge carbons is firstly discovered.•The theory calculations unveil the mechanism of edge carbons facilitating the ORR.

The oxygen reduction reaction (ORR) has been investigated on fish-bone carbon nanotubes (F-CNTs) and parallel carbon nanotubes (P-CNTs). The results showed that the F-CNTs exhibited much higher activity than P-CNTs, which originated from the higher fraction of edge carbon atoms. The dependence of ORR peak potential on the fraction of edge carbon atoms was determined quantitatively for the first time. The density functional theory calculations clearly unveiled the mechanism of edge carbon atoms facilitating the ORR performance.

Graphical abstractThis study proves that the electrocatalytic oxygen reduction reaction (ORR) occurs more easily on edge carbons than on basal carbons of carbon nanotubes.Figure optionsDownload full-size imageDownload as PowerPoint slide