One-Step Preparation of Strongly Luminescent and Highly Loaded CdSe Quantum Dot-Silica Films

Abstract

Strongly luminescent and highly loaded CdSe quantum dot (QD)-silica composite films are prepared by a simple one-step method. QDs are grown in situ as the silica matrix forms from spin-on-glass organosiloxane polymers. The nucleation and growth of QDs in the silica matrix is directly observed using TEM. The QD composites are comprehensively characterized, which includes photoluminescence(PL) decay, PL efficiency, and QD volume fraction. The QD emission can span the entire visible range and can be tuned by the preparation condition. The PL of QDs is very strong, reaching the quantum efficiency up to 35%. Very high QD loading is achieved with the volume fraction as high as 13%, which makes our composite the highest loaded QD-silica composite material. We further showcase the versatile applicability of our method by a QD-silica composite capped down-conversion pseudo white LED.