Efficient Dynamic Potential Stabilization via a Bioinspired Ion Pump Prevents Sensing Signals Drift.

Abstract

Artificial ion-sensing systems rely on external power to sustain interfacial potentials, facing persistent stability challenges. During continuous operation, progressive energy depletion results in potential decay, manifesting as signal drift and eventual system failure. This problem stems from the absence of an efficient active regulation mechanism analogous to biological ion pumps, which harness ATP hydrolysis to actively transport ions against electrochemical gradients, dynamically compensating for potential dissipation. Inspired by this mechanism, we developed an oxygen-driven bioinspired ion pump that exploits oxygen-sensitive O─Zn bonds within NH₄ ⁺-intercalated V₂O₅ to achieve efficient Zn²⁺ extraction and reverse pumping in oxygen-rich environments, successfully emulating biological active transport. This design enables sustained electrode potential stability through dynamic ion pumping while significantly enhancing the ion-storage capacity of V₂O₅. Theoretical simulations elucidated the mechanism linking O─Zn bond dissociation to adsorption site energy states under oxygen enrichment, alongside the resulting Zn²⁺ pumping process. The constructed self-powered respiration sensor demonstrated stable operation for 480 h in ambient air without external power, exhibiting a minimal performance degradation rate of only 0.2% (compared to 13.9% in oxygen-free environments). This work proposes an oxygen-driven bioinspired ion-pumping strategy, offering a novel pathway to overcome persistent energy supply challenges in potentiometric sensors.