Manipulating Photoisomerization Rate of Triphenylethylene Derivative through Metal Coordination for Irradiation Time‐Dependent Information Encryption

Abstract Achieving on‐demand control of responsive behaviors of photochromic molecules is important for advanced photonic applications, but it remains a challenge. In this work, a triphenylethylene‐based molecule, 5‐(2,2‐bis(4‐fluorophenyl)vinyl)‐5″‐methyl‐2,2″‐bipyridine ( 1 ), which can undergo open‐to‐closed isomerization under 365 nm irradiation, is designed and synthesized. Importantly, on‐demand acceleration or deceleration of photoisomerization rate over a wide range ( k UV = 0.00584–0.06299 s −1 ) is achieved by coordination of 1 with different metal salts. Furthermore, more precise manipulation of the photoisomerization rate is achieved by changing the counterions of the 1 ‐based metal complex. Eventually, taking advantage of distinctly different photoisomerization rates of 1 and its corresponding metal complexes, high‐level irradiation time‐dependent information encryption and anticounterfeiting applications have been demonstrated.