A Ni-Fe layered double hydroxide anchored FeCo nanoalloys and Fe-Co dual single-atom electrocatalysts for rechargeable and flexible zinc-air and aluminum-air batteries

Developing bifunctional catalysts for the ORR and OER, along with a unique cathode structure, is essential for advancing rechargeable zinc-air batteries (ZABs) and aluminum-air batteries (AABs). Our catalyst (NiFe LDH A-FeSACoSA-FeCoAlloy-CNT/NC) integrates nickel-iron layered double hydroxide (NiFe LDH), iron-cobalt dual single atoms (FeSACoSA), and iron-cobalt nanoalloy (FeCoAlloy) within carbon nanotubes (CNTs) on a nitrogen-doped carbon framework (NC). Due to its distinctive features, this catalyst excels, achieving an ORR half-wave potential of 0.84 V and an OER potential of 1.56 V (E-j=10mAcm(-2)). In ZABs, it outperforms the Pt/C+RuO2, reaching a power density of 266 mWcm(-2) and demonstrating impressive rechargeability over 495 h (1484 cycles). Flexible ZABs achieve 173 mWcm(-2) and over 270 cycles (90 h), while flexible AABs reach 145 mWcm(-2), surpassing Pt/ C+RuO2. Exceptional performance in terms of capacity, power density, rechargeability, and lifespan is attributed to the catalyst's design and the cathode configuration's unique attributes.