Tackling Solid‐Contact Sensor Drift Using Conductive Metal Organic Frameworks as Ion‐to‐Electron Transducers

ABSTRACT Solid‐contact ion‐selective electrodes (SC‐ISEs) are widely used electrochemical sensors for measuring ionic concentrations with high sensitivity and selectivity. However, their reliability is often compromised by fundamental challenges such as water‐layer formation, limited charge‐storage capacitance, and the resulting potential drift that degrades long‐term accuracy. This review explores the emerging application of conductive metal–organic frameworks (MOFs) as a novel class of ion‐to‐electron transducers designed to address these persistent limitations. Conductive MOFs offer several key advantages, including high porosity, large electroactive surface area, and intrinsic electrical conductivity, that collectively enable efficient ion‐to‐electron transfer and enhanced interfacial stability. Recent studies demonstrate that MOF‐based solid contacts can provide high capacitance, minimize water‐layer formation, and substantially reduce drift, outperforming many traditional transducers such as conducting polymers, carbon nanomaterials, and metal‐based layers. This review summarises the progression of MOF‐based SC‐ISEs from early proof‐of‐concept demonstrations to more advanced composite and flexible platforms. Despite challenges such as potential instability in acidic environments and synthesis‐related constraints, growing evidence shows that chemically robust and highly conductive MOFs hold significant promise for next‐generation SC‐ISEs. Continued innovation in the design and integration of these novel materials may offer an effective pathway for overcoming long‐standing drift issues and enabling reliable long‐term ion monitoring across environmental, biomedical, and industrial applications.