Pyrochlore LaSrSn2O7 nanoparticles anchored on carbon nanofibers as bifunctional catalysts for an efficient Li-O2 battery
Jong Guk Kim, Yuseong Noh, Youngmin Kim
Abstract
The slow reaction kinetics of oxygen reduction reaction for Li2O2 formation and oxygen evolution reaction for Li2O2 decomposition with poor electrocatalytic activities have been a problem to be solved for the commercialization of lithium-oxygen (Li-O2) batteries. Bifunctional catalysts composed with pyrochlore LaSrSn2O7 nanoparticles (LSSO NPs) and one-dimensional (1D) carbon nanofibers (NFs) were prepared and their catalytic performances were investigated for Li-O2 batteries. As-obtained 1D carbon@LaSrSn2O7 (C@LSSO) NFs composites in Li-O2 battery cathode delivered excellent initial specific capacity (ca. 8067.3 mAh g−1). In addition, decent cycle durability of the C@LSSO cathode was accomplished over 54 cycles with a low overpotential gap of 1.01 V at a rate of 200 mA g−1 with a specific capacity limit of 500 mAh g−1, in comparison to the LSSO NPs and ketjen black carbon. The enhanced properties suggest that these composite structures of pyrochlore LSSO NPs with 1D carbon NFs backbones could be a prospective bifunctional catalyst in the development of the high-performance Li-O2 battery.