Facile preparation of glycine-based mesoporous graphitic carbons with embedded cobalt nanoparticles

Abstract

A simple route has been developed for the preparation of mesoporous graphitic carbons with embedded cobalt nanoparticles just using glycine as a nitrogen source, cobalt nitrate and distilled water. After heating the mixture to 300 °C under magnetic stirring, a dry solid product was obtained, which was then carbonized at 900 ºC under argon atmosphere. Changing the glycine/Co molar ratio allowed controlling the size of the cobalt particles and their dispersion in the carbon matrix, the porosity of the carbon and its graphitic character. The carbon–metal composites obtained were tested as oxygen cathodes in Li–O2 batteries. Cells assembled exhibited a full discharge capacity up to 2.19 mAh cm−2 at a current of 0.05 mA cm−2 and over 39 cycles at a cutoff capacity of 0.5 mAh cm−2. This work provides a green, feasible and simple way to prepare mesoporous graphitic carbons with embedded cobalt nanoparticles without involving templates. Graphical abstract: [Figure not available: see fulltext.].