Sustainable multifunctional zinc oxide quantum dots-aided double-layers security paper sheets

Mohamed S Hasanin; Mona Nassar; Youssef R Hassan; Łukasz Piszczyk; Mohammad Reza Saeb; Agata Kot-Wasik

doi:10.1016/j.heliyon.2023.e14695

Sustainable multifunctional zinc oxide quantum dots-aided double-layers security paper sheets

Heliyon. 2023 Mar 21;9(4):e14695. doi: 10.1016/j.heliyon.2023.e14695. eCollection 2023 Apr.

Authors

Mohamed S Hasanin¹, Mona Nassar², Youssef R Hassan², Łukasz Piszczyk³, Mohammad Reza Saeb³, Agata Kot-Wasik⁴

Affiliations

¹ Cellulose and Paper Department, National Research Centre, Dokki, 12622, Cairo, Egypt.
² Packaging Materials Department, National Research Centre, Dokki, 12622, Cairo, Egypt.
³ Department of Polymer Technology, Faculty of Chemistry, Gdańsk University of Technology, Narutowicza 11/12, Gdańsk, Poland.
⁴ Department of Analytical Chemistry, Faculty of Chemistry, Gdańsk University of Technology, 11/12 Narutowicza Str., Gdańsk, 80-233, Poland.

Abstract

Fluorescence is well-known nowadays as one of the most efficient anti-counterfeiting techniques. Zinc oxide quantum dots (ZnOQds) are exceptionally fluorescence when exposed to ultraviolet (UV) light, which makes them a candidate for anti-counterfeiting printing. The resulting anti-counterfeiting papers are sustainable and resistance against organic dyes. In this work, ZnOQds were prepared via a green method and characterized under UV-visible spectroscopy, along with microscopic observations by transmission electron microscopy (TEM) and crystallography by X-ray diffraction (XRD). Formation of ZnOQds nanocrystals with an average partials size of 7.3 nm was approved. Additionally, double-layers sheets were prepared at two loading concentrations of ZnOQds, namely 0.5 and 1 (wt./v) and underwent characterization using a topographical surface study via field emission scanning electron microscopy (FE-SEM). Hybrid sheets were mechanically more stable compared to single-layer paper and likewise polymer film. Moreover, aging simulation approved a high stability for hybrid sheets. Particularly, the photoluminescence emission affirmed anti-aging character of hybrid paper for more than 25 years. The hybrid sheets also showed a broad range of antimicrobial activity.

Keywords: Aging; Anti-counterfeiting; Antimicrobial activity; Mechanical properties; ZnOQds.