Amelioration of the UV-blocking property of ZnO nanoparticles as an active sunscreen ingredient

Abstract

ZnO nanoparticles are synthesized employing simple wet chemical methods and different samples are prepared by varying liquid mediums (consecutively water medium, ethanol medium, methanol medium) in the initial solution. All samples are evaluated for optical, microstructural, and compositional characteristics. The UV-vis spectra of ZnO nanoparticles show interesting and remarkable changes with varying synthesis conditions. The fascinating observation of generating high %UVA-blocking and %UVB-blocking can be attributed to getting control over the UV-vis spectra of synthesized ZnO nanoparticles. These NPs can provide full protection from total UV region due to their high %UVA-blocking and %UVB-blocking values. When the experimental settings are changed (from water medium to ethanol medium then to methanol), the % UVA-blocking and % UVB-blocking is highest for the sample synthesized in methanol medium, lower for the sample synthesized in ethanol medium and lowest for the sample synthesized in water medium. The facile technique adopted in this work opens up an easy way to synthesize ZnO nanoparticles (NPs) with a broad absorption spectrum in the UV area and can provide full protection from the whole UV range.