A research team led by Professor HUANG Xingjiu at the Hefei Institutes of Physical Science of the Chinese Academy of Sciences has developed a highly stable adaptive integrated interface for ion sensing.

The study was published as an inside front cover article in Advanced Materials.

All-solid-state ion-selective electrode serves as a fundamental component in the ion sensing of intelligent biological and chemical sensors. While the researchers had previously developed several transducer materials with a sandwich-type interface to detect common ions. The performance of such sensors was often limited by interface material and structure.

To overcome these challenges, the team introduced a novel interface using lipophilic molybdenum disulfide (MoS₂) regulated by cetyltrimethylammonium (CTA⁺). This structure enables spatiotemporal adaptive integration—assembling single-piece sensing layers atop efficient transduction layers.

Electrochemical simulations confirmed the superior stability of the new interface, demonstrating high charge transfer efficiency and low diffusion current. X-ray Absorption Fine Structure analysis revealed a mixed-capacitance mechanism driven by TFPB⁻ anion adsorption.

When applied to cadmium ion (Cd²⁺) detection, the sensor exhibited excellent stability and maintained high accuracy in real-world testing scenarios, including industrial wastewater environments.

The interface was successfully extended to sensors for detecting a range of ions, including K⁺, Na⁺, Ca²⁺, Mg²⁺, Pb²⁺, Cd²⁺, and Cu²⁺. All showed near-Nernstian responses with significantly enhanced stability.

This work provides a valuable strategy for designing next-generation high-performance ion sensors.

The inside front cover article in Advanced Materials. (Image by CAI Xin)