Nitrogen-Doped Carbon Nanosheets Supported Co for Efficient and Stable Electrocatalytic Oxygen Reduction
Xin Liu, Jiabing Luo, Xinyu Liu, Shutao Wang, Wenle Li, Jun Zhang, Yan Zhou
Abstract
Designing highly efficient non-noble metal electrocatalysts to replace state-of-the-art noble metal electrocatalysts such as Pt is crucial for large-scale application of hydrogen fuel cells. In this paper, we proposed a facile synthetic strategy using metal–organic framework material as a template to achieve evenly distributed Co nanoparticles (Co NPs) on the N-doped carbon nanosheets with high specific surface area and electrocatalytic activity toward the oxygen reduction reaction (ORR). The presence of pyrrolic N modulated the electronic structure of Co to promote the ORR catalytic activity while hindering the Co NPs from aggregation. The results show that the carbon nanosheet-supported Co NPs have the best ORR electrocatalytic activity at an optimal annealing temperature (900 °C). The electrocatalyst exhibited an onset potential ( E onset ) of 0.96 V vs . RHE and a half-wave potential ( E 1/2 ) of 0.89 V vs . RHE, which outperformed the commercial 20% Pt/C. At the same time, it also showed better oxygen evolution reduction and zinc–air battery (ZAB) performance than commercial RuO 2 and 20% Pt/C. Therefore, this work can provide guidance for the design and synthesis of multifunctional non-noble metal electrocatalysts for future ZAB applications.