Formation of Photo-Luminescent Patterns on Paper Using Nanocrystalline Quantum Dot Ink and Mist Deposition

Abstract

This study explores patterned deposition of cadmium selenide (CdSe) nanocrystalline quantum dot (NQD) thin films on paper substrates using the process of mist deposition. Potential applications of the process include security/anti-counterfeiting patterns and identification labels. Barcode-like patterned NQD films were successfully deposited on a range of substrates, including various types of paper. The films were characterized for fluorescence intensity, spectrum and quality of pattern transfer from shadow mask to the deposited film. Time dependent degradation of the deposited pattern was among key aspects investigated. The results obtained indicate that NQD films deposited on paper and protected against exposure to ambient air using plastic laminate maintain integrity and show negligible degradation in photoluminescence intensity over a period of several weeks.