Nitrogen-Doped NiCo₂O₄ Microsphere as an Efficient Catalyst for Flexible Rechargeable Zinc–Air Batteries and Self-Charging Power System

The design and synthesis of efficient and cost-effective electrocatalysts are vital for rechargeable zinc–air batteries (ZABs). Here, nitrogen-doped NiCo 2 O 4 (N-doped NiCo 2 O 4 ) was prepared and used as a promising electrocatalyst for ZABs. By doping with nitrogen, the N-doped NiCo 2 O 4 catalyst shows higher catalytic activity than that of NiCo 2 O 4 in terms of higher half-wave potential and lower Tafel slope. As a cathode catalyst for flexible rechargeable zinc–air batteries, the cell with N-doped NiCo 2 O 4 shows excellent cycling performance. X-ray absorption near-edge structure (XANES) results manifest that the improved catalytic performance is attributed to the enhanced covalence of Co–O and Ni–O and more active sites in N-doped NiCo 2 O 4 . Moreover, we demonstrate a self-powered system, which integrates the flexible ZABs and TENG to power a LED screen.