Wearable electrochemical sensor for real-time sweat monitoring powered by Li–S battery: Rapid ion-electron transduction driven by high-entropy Prussian blue analogues

Abstract

The portable electrochemical sensors couple with high-energy density batteries lay the foundation for intelligent electronic devices capable of real-time and long-term monitoring of signals at the molecular level. Currently, high-entropy materials play a crucial role in advanced energy storage system and electroanalytical chemistry due to their powerful multi active centers and lattice strain fields. Herein, we propose high-entropy Prussian blue analogues (HE-PBA) as a bidirectional catalyst to reduce the activation energy of sulfur redox reaction, alleviate polysulfides shuttle, and inhibit lithium dendritic growth in Li–S battery. Furthermore, benefited from hierarchical HE-PBA with multiple redox active sites, superior ion-selective effect, high ionic/electrical conductivity and hydrophobicity, thus contributing to splendid ion-electron transducer capability as solid contact layer in wearable potentiometric electrochemical sensors. As a result, an advanced wearable electronic device integrates LSB as a power source with potentiometric electrochemical sensor unit equipped with ion selective electrode, enabling real-time monitoring of K⁺ concentration in sweat metabolite during outdoor exercise. In a word, this work demonstrates a tremendous potential of designing multifunctional electrode materials for advanced energy storage and electrochemical sensing applications through high entropy strategies.