Design of a ZnO@Plant Polyphenol/Poly(vinyl alcohol) Film via Plant Polyphenol-Induced Cross-Linking and Its Enhanced UV Shielding and Antibacterial Performance

Biomaterial utilization in a highly value-added way is a key factor in promoting sustainable development of the human society. Herein, plant polyphenol (PPL), extracted from larch pine bark, has been exploited to synthesize ZnO@PPL. Its microstructures and morphology were examined by experimental techniques in conjunction with density functional theory calculations. Small pinecone-like particles of ZnO@PPL are accessible. As a coating layer, PPLs play two roles: (1) chemically couple with ZnO and control its size and (2) cross-link with each other and make ZnO slices build up a hierarchical structure. It has been found that ZnO@PPL bears good ultraviolet (UV) shielding performance by covering the entire UV light range. The fabricated ZnO@PPL/poly(vinyl alcohol) (ZnO@PPL/PVA) film inherits a remarkable UV shielding ability and blocks almost 100% irradiation between 200 and 420 nm. Moreover, the antibacterial activity and mechanism are also addressed.