High-performance
rechargeable oxygen electrodes are key devices
for realizing high-specific-energy batteries, including zinc–air
and lithium–air batteries. However, these batteries have severe
problems of premature decay in energy efficiency by serious corrosion,
wide charge–discharge gap, and catalyst peeling off. Herein,
we propose a “smart dual-oxygen electrode”, which is
composed of an intelligent switch control module + heterostructured
Fe1Ni3-LDH/PNCNF OER catalysis electrode layer
+ ion conductive | electronic insulating membrane + Pt/C ORR catalysis
electrode layer, where OER and ORR layers are automatically switched
by the intelligent switch control module as required. This smart dual-oxygen
electrode offers an ultralow energy efficiency decay rate of 0.0067%
after 300 cycles during cycling, much lower than that of the commercial
Pt/C electrode (1.82%). The assembled rechargeable zinc–air
battery (RZAB) displays a super narrow voltage gap and achieves a
high energy efficiency of 71.7%, far higher than that of the existing
RZABs (about 50%). Therefore, this strategy provides a complete solution
for designing various high-performance metal–air secondary
batteries.