Batch preparation process of composite materials of quantum dot glass and polystyrene used in backlight displays

Abstract

All-inorganic CsPbX3 quantum dots (X = Cl, Br, or I) are regarded as a new generation of efficient luminescent materials for displays and solid-state lighting due to their excellent optoelectronic properties. However, the poor stability of CsPbX3 quantum dots severely hampers their commercial applications. Currently, the in-situ growth of CsPbX3 quantum dots in amorphous glass has emerged as a crucial approach to significantly enhance their stability. This study successfully synthesized large-scale CsPbBr3@glass materials using a one-step self-crystallization method involving melting, quenching, and heat treatment. CsPbBr3@glass was blended with polystyrene (PS) through melt blending and extrusion, resulting in the fabrication of a CsPbBr3@glass@PS film. By controlling the content of quantum dot glass in polystyrene and adjusting the film's thickness, a green light film with color coordinates (0.1629, 0.7759) and a Full Width Half Maximum (FWHM) of 19.78 nm was achieved. The film produced through this process demonstrated exceptional stability, retaining 90% of its luminous intensity after 1000 h of rigorous aging experiments. Furthermore, when combined with potassium fluorosilicate composite polystyrene film and a blue light chip, a 7-inch LCD display with a color gamut of 135.8% of NTSC 1953 and 92.8% of Rec. 2020 was successfully assembled. This research holds significant reference value for the commercial application of quantum dot glass.