Achieving high cycling stability in alkaline zinc-iron flow batteries through synergy of 3D VPCF/nicotinamide and active ZnO species

• Synergistic combination of 3D VPCF, nicotinamide, and ZnO additives significantly enhances cycling stability of alkaline zinc-iron flow batteries. • The system achieves 99.9% capacity retention over 1000 cycles at 5 mA/cm2, demonstrating exceptional long-term durability. • Nicotinamide suppresses zinc dendrite growth and regulates deposition behavior, while ZnO optimizes nucleation and electrolyte conductivity. • This work provides a novel pathway for developing stable and cost-effective zinc-based energy storage systems for renewable energy integration.