Fluorescent Patterning of Polymeric Substrates with Rare-Earth-Doped Nanophosphors Assisted by Atmospheric Pressure Plasma

The direct, efficient, and controllable patterning of fluorescent materials on polymers is crucial for fundamental research and industrial application but very challenging. Herein, a DBD plasma method was used to deposit rare-earth-doped nanophosphors on the surface of polymeric substrates without thermal annealing steps, aiming to realize fluorescent patterning of thermally sensitive polymers through a simple and low-temperature process. Eu- and Tb-doped yttria (Y2O3) nanoparticles of different fluorescence properties were synthesized from rare-earth acetylacetonates to verify the feasibility of the process, followed by the formation of desirable fluorescent patterns on poly(vinylidene difluoride) (PVDF) membranes using relief printing to demonstrate the flexibility of this novel strategy. The results showed that crystalline rare-earth-doped Y2O3 nanophosphors were rapidly generated in plasma and can be deposited on the PVDF membranes to form fluorescent patterns without damaging the polymeric substrates. This method was further expanded to diverse substrates like polypropylene (PP), polyether sulfone (PES), and nylon, revealing the versatility of direct fluorescent patterning on thermally sensitive polymers. The efficient, flexible, and rapid plasma process combined with the desirable high-fluorescence patterns is expected to supply guidance for the design and fabrication of functional polymers.