Achieving Swift and Distinct Luminescent Modulation Through Manipulating Molecular Motion in Polymers

Abstract Molecules in the bulk state are typically constrained by multiple intermolecular interactions, making it challenging to develop emission‐tunable solid‐state materials. Manipulating molecular motion is essential for achieving dynamic solid‐state emissions. Herein, various emission‐tunable 4CN@polymer films are developed whose multicolor luminescence arises from different molecular motion modes within the polymer microenvironments. There are three motion modes in the films: restricted, normal, and vigorous. In the normal mode, the film emits green light, shifting to purple under UV (515–387 nm). Cooling or fuming creates a rigid environment, leading to blue emission at 426 nm. High temperatures induce vigorous motion, causing quenched emission, which can be reactivated by cooling. This mechanism underscores the significant influence of molecular motion within flexible polymers on the luminescence behavior of 4CN@polymer films, enabling multicolor emission based on environmental conditions. The wide‐range fluorescence—from purple, blue, white, green, yellow‐green to dark—indicates promising applications in multifaceted dynamic displays and information security. This study offers novel perspectives on the correlation between solid‐state molecular motion and dynamic emission.