Ultraviolet‐shielding and water resistance properties of graphene quantum dots/ polyvinyl alcohol composite-based film

The Ultraviolet‐shielding (UV‐shielding) and water resistance properties of graphene quantum dots/polyvinyl alcohol (GQDs/PVA) composite-based film have been investigated. The GQDs/PVA composite-based films were fabricated with different GQDs concentrations of 0, 5, 10, 15, and 20 wt%. The optical property of GQDs was carried out by utilizing fluorescence spectroscopy. Characterizations of GQDs/PVA composite-based films were performed by using FT-IR spectroscopy, and UV-vis spectroscopy. It was found that GQDs exhibited the strongest excitation wavelength in the UV range. GQDs/PVA composite-based films offered an improved UV-shielding capacity when compared to PVA films and glass. Particularly, the GQDs/PVA composite-based film containing 20 wt% GQDs exhibited a UV transmittance of 9.8%, combined with 84% optical transparency. For humidity environment application, the highest contact angle was explored for the 10 wt% GQDs contents suggesting sustainability for humidity environment application. Accordingly, GQDs played an important role in UV-shielding by considering the effect of UV absorption of GQDs and the UV absorption of GQDs can be explained in terms of the photon excitation by UV light. This GQDs/PVA composite could be potentially applied as transparent UV-protective coatings for pharmaceutical packing, food products packing, and UV-shielding or UV filter glass.