Direct Ink Writing of Quantum Dot Nanoparticles by Robocasting Apparatus for Precise Light-Emitting Patterns

In this study, colloidal quantum dot nanoparticles were prepared by wet chemical synthesis protocol to obtain quantum dot nano-inks for the formation of patterned light-emitting surfaces. The synthesized Cd(S, Se) quantum dot nanoparticles were mixed with polymeric matrix such as poly(styreneco-methylmethacrylate) and toluene as dispersion medium. The combined operation of robocaster and dispensing module resulted in the formation of precise patterns according to the G-code design. Then, UV irradiation to the printed region caused the visible light emission from the pattered surfaces composed of the semiconducting nanoparticles, which can be potentially applicable to the display pixels.