A light/pH/multiple ion-driven smart switchable module for computing sequential logic operations via a resettable dual-optical readout

A switchable module comprising pendant pyridine groups, an amide linkage and a photoswitchable functionality (azobenzene) has been designed and characterized via a full battery of physico-chemical techniques. The module has been exploited for ternary/binary data storage with non-destructive optical identity owing to its high photo-stability, excellent reversibility, and chemical-/photo-switchability. Moreover the module exhibits sequential logic gate-based detection of multiple ions (Cu 2+ , CN − , F − and I − ) at ppm levels via a “turn on” signature which potentially meets real-world challenges in terms of the simple synthesis route, rapid response, water based activity, naked-eye visualization, regenerative action, high selectivity and multiple readout for precise analysis.