Influence of Calcination Temperature on Performances of Co-N/C Electrocatalysts for Li/O2 Cells

The development of low-cost and effective electrocatalysts for air electrodes is critical for practical applications of lithium/oxygen batteries. In the present work, phenanthroline (phen) was used as a ligand to prepare a Co(phen)2 complex. The Co(phen)2 complex was coated on BP2000 and then heat treated at 600, 700, 800, and 900 , to obtain carbon-supported Co-N (Co-N/C) catalysts. The catalytic activities in oxygen reduction reaction/oxygen evolution reaction (ORR/OER) of the prepared catalysts were measured and compared with those of a typical carbon-supported cobalt tetramethoxyphenylporphyrin (CoTMPP/C) catalyst. The influence of the calcination temperature on the composition and structure of the Co-N/C catalysts was investigated. Electrochemical tests showed that the Co-N/C catalysts prepared at 700 and 800 gave better performances, comparable to that of the CoTMPP/C catalyst. The superior electrochemical performance of the prepared Co-N/C catalysts and the low cost of the phenanthroline chelating agent make Co-N/C a promising cheap catalyst for lithium/oxygen batteries.