Tailoring lithium-peroxide reaction kinetics with CuN2C2 single-atom moieties for lithium-oxygen batteries

Abstract

Single-atom catalysts (SACs) featuring maximized atom utilization are, in no doubt, playing an increasingly significant role in aprotic lithium-oxygen batteries (LOBs). However, rational design and construction of SACs active sites remain enormously challenging due to the superficial understanding of their structure-function relationship. In this contribution, we provide new insight into the link between the catalytic effects of catalysts and the detailed nucleation/delithiation mechanisms of Li2O2 during the oxygen reduction/evolution reaction (ORR/OER). Here, a CuN2C2 SACs electrocatalyst is tailored for LOBs by a confined self-initiated dispersing strategy. The exposed Cu-N2 moieties as the driving force centers can promote the formation of micron-sized flower-shaped lithium peroxide and further accelerate the decomposition kinetics of lithium peroxide via a one-electron transfer way in turn. Under the catalysis of CuN2C2 SACs, the LOB can operate with low discharge/charge polarization and long-term cycle stability. These encouraging results provide guidance to future design and activity promotion of efficient catalysts for LOBs.