Temporal Decoupling: A New Paradigm of 4D Photo‐Responsive Carbon Dots Films With Modular Regulation of Color and Deformation

ABSTRACT

To address the key bottlenecks of traditional photo‐responsive 4D materials, namely the inability to achieve independent regulation of photoinduced deformation and multicolor fluorescence, and the insufficient security of encryption systems, this study takes naphthalimide‐functionalized carbon dots (CDs) as the core functional unit, and for the first time proposes and verifies a novel energy regulation strategy using the long‐lived S ₁ transition as a “kinetic capacitor”. This strategy enables dual‐channel programmable shunting of excited‐state energy: radiative relaxation for fluorescence emission, and non‐radiative relaxation‐generated photothermal effect for deformation driving. By adjusting the feeding ratio of triethanolamine to tune the HOMO‐LUMO energy gap, multicolor fluorescence from blue to orange‐red is achieved. On this basis, this study successfully constructs two independent regulation systems, including photothermally driven deformation and S ₁ state energy level‐tuned photo‐responsive multicolor fluorescence, and fabricates 4D photo‐responsive smart films with the characteristic of temporally decoupled integration of photo‐responsive multicolor fluorescence and photoinduced deformation. Relying on the irreversible photo‐response properties and the difference in photo‐response time of the materials, a three‐dimensional dynamic single‐use anti‐counterfeiting model is established, which provides a new approach for the modular design of 4D smart materials and their high‐end anti‐counterfeiting applications.