Paper Air Cathodes with One-Dimensional Perovskite Nanofiber for Origami-Foldable/Rechargeable Zn-Air Batteries

Abstract

To satisfy the demand for flexible/wearable electronics, we demonstrate paper air cathodes to fabricate foldable Zn-air batteries with reliable electrochemical rechargeability. The paper air cathodes consist of one-dimensional (1D) bifunctional catalyst mixtures (NdBa0.5Sr0.5Co1.5Fe0.5O5+δ layered perovskite (NBSCF) nanofibers and nitrogen-doped carbon nanotubes (N-CNT)), cellulose nanofibers (CNF), and polytetrafluoroethylene (PTFE). The PTFE and CNF act as hydrophobic and hydrophilic binders, respectively, to construct three-dimensional (3D) bicontinuous air/electrolyte channels in the paper air cathodes. The well-combined electrolyte/air transport pathways allow the Zn-air batteries to exhibit highly efficient charge/discharge performance and cyclability. Moreover, the highly entangled network structure of the paper air cathode enhances mechanical flexibility, allowing the Zn-air battery to be folded into a paperairplane shape through origami folding.