CeO2 nanodots decorated ketjen black for high performance lithium-sulfur batteries

A CeO2 nanodots decorated ketjen black composite was fabricated by a simple wet impregnation method and used as the host of sulfur for a lithium-sulfur battery. The microstructure and chemical components were evaluated by XRD, SEM, TEM, surface area analysis and thermogravimetric analysis. Electrochemical tests and microanalysis demonstrated that CeO2 nanodots served as the sulfur fixation spots as well as the catalytic agent compared with the reference sample without CeO2 nanodots. The CeO2/KB-S cathode material with the CeO2/KB mass ratio of approximately 15/85 shows a high initial discharge capacity of 905 mA h g(-1) at the current rate of 1C and remains at 710 mA h g(-1) after 300 cycles. Furthermore, the CeO2/KB-S cathode shows a promising rate performance with the discharge capacity of 800 mA h g(-1) even at the current rate of 2C.