Carbon‐Free Cathode Materials for Li−O2 Batteries

Abstract Rechargeable lithium‐oxygen batteries, especially the nonaqueous lithium‐oxygen batteries have attracted much attention in recent years due to their high energy densities. However, few critical challenges remain to be overcome, including the low round‐trip efficiency, high charge overpotential, poor cycling performance, decomposition of electrolyte, and instability of the carbon‐based electrode. Among these, the instability of the carbon‐based electrode is one of the major problems that hindered the practical application of the Li−O 2 batteries. Much work has been done to solve this problem and there are two widely‐applied strategies: modification of carbon and designing a “carbon‐free” cathode. In this review, we will introduce recent achievements of both strategies.