Single non-noble-metal cobalt atom stabilized by pyridinic vacancy graphene: An efficient catalyst for CO oxidation

•The non-noble-metal cobalt could be strongly stabilized by pyridinic N vacancy.•The activated sites of Co-N3-gra are identified.•The L-H mechanism is more preferable for CO oxidation than the E-R mechanism.•The Co-N3-gra catalyst exhibits higher catalytic activity for CO oxidation than some other noble metal catalysts.

The low operating temperature, high efficiency and noble-metal-free are the goal of the ideal catalysts. In present study, an efficient noble-metal-free catalyst for CO oxidation with a single cobalt atom incorporated with pyridinic nitrogen graphene (Co-N3-gra) is proposed. The catalytic activity for CO oxidation via various mechanisms on the Co-N3-gra catalyst is investigated using the first-principles method. It is found that the CO oxidation occurs preferably following the Langmuir-Hinshelwood mechanism (CO + O2 → OOCO → CO2 + O) with an energy barrier of 0.86 eV for the rate-limiting step of OOCO formation. Our findings prove that the activity of noble-metal-free Co-N3-gra catalyst is comparable to or even higher than some other single noble-metal-graphene based catalysts.

Graphical abstractCO oxidation catalyzed by the non-noble metal Cobalt coupled with pyridinic N3 graphene along the Langmuir-Hinshelwood mechanism.Figure optionsDownload full-size imageDownload high-quality image (271 K)Download as PowerPoint slide