<p>NH₄V₄O₁₀ (NVO) is considered a promising cathode material for aqueous zinc-ion batteries due to its high theoretical capacity. However, its practical application is limited by irreversible deamination, structural collapse, and sluggish reaction kinetics during cycling. Herein, K⁺ and C₃N₄ co-intercalated NVO (KNVO-C₃N₄) nanosheets with expanded interlayer spacing are synthesized for the first time to achieve high-rate, stable, and wide-temperature cathodes. Molecular dynamics and experimental results confirm that there is an optimal C₃N₄ content to achieve higher reaction kinetics. The synergistic effect of K⁺ and C₃N₄ co-intercalation significantly reduces the electrostatic interaction between Zn²⁺ and the [VO_n] layer, improves the specific capacity and cycling stability. Consequently, the KNVO-C₃N₄ electrode displays outstanding electrochemical performance at room temperature and under extreme environments. It exhibits excellent rate performance (228.4 mAh g⁻¹ at 20 A g⁻¹), long-term cycling stability (174.2 mAh g⁻¹ after 10,000 cycles at 20 A g⁻¹), and power/energy density (210.0 Wh kg⁻¹ at 14,200 W kg⁻¹) at room temperature. Notably, it shows remarkable storage performance at − 20 °C (111.3 mAh g⁻¹ at 20 A g⁻¹) and 60&#xa0;°C (208.6 mAh g⁻¹ at 20 A g⁻¹). This strategy offers a novel approach to developing high-performance cathodes capable of operating under extreme temperatures.</p>