Surface modification toward luminescent and stable silica-coated quantum dots color filter

Abstract

A highly pixelated and luminescent silica-coated quantum dot color filter (QDCF) was achieved by surface conjugation with epoxy functional group. Epoxy-functiona-lized silica-coated quantum dots (QDs) can be thoroughly mixed with SU-8 photoresist up to 25 wt.% without aggregation. The quantum yield (QY) of the silica-coated QDCF can be significantly improved from 19.3% to 36.5% after epoxy treatment. The pristine QDCF experienced a 40% QY decrease, while the epoxied silica-coated QDCF maintained its luminescence even after irradiation (300 mW cm −2 @450 nm) for over 25 days. The well-controlled epoxy cap plays a critical role in attaining the ideal optical properties of the QDCF.