Interface engineering of Ruddlesden–Popper perovskite/CeO2/carbon heterojunction for rechargeable zinc-air batteries

The development of noble metal-based bifunctional electrocatalysts is the key to driving the sluggish oxygen reduction/evolution reaction (ORR/OER) for rechargeable zinc-air battery applications. There is an urgent need to design and construct robust and cost-efficient bifunctional electrocatalysts . Herein, an interface engineering strategy of Ruddlesden–Popper (RP) perovskite/CeO 2 /carbon heterojunction with core–shell nanostructures is described. Ce-based metal–organic framework derived CeO 2 -C nanosheets are decorated on the surface of RP type perovskite Pr 3 Sr(Ni 0.5 Co 0.5 ) 3 O 10−δ (PSNC) nanofibers . Benefiting from the favorable conductivity, abundant oxygen vacancies and strong interfacial coupling, the hierarchical CeO 2 -C/PSNC electrode delivers a half-wave potential of 0.78 V (ORR), and an OER overpotential of 370 mV at 10 mA cm −2 , respectively. A liquid rechargeable zinc-air battery (ZAB) assembled with CeO 2 -C/PSNC electrocatalysts as the air cathode exhibits a peak power density of 161 mW cm −2 and a long-term cycling life over 219 h. In addition, the CeO 2 -C/PSNC-based all-solid-state cable-type ZAB provides a high open-circuit voltage (∼1.44 V), good flexibility and durability. Our study opens a new insight into the design of efficient electrocatalysts for rechargeable ZABs by constructing hierarchical heterojunctions.