Toward efficient broad-spectrum UV absorption of carbon dots: Facile preparation, performance characterization and its application as UV absorbers

다국어 초록 (Multilingual Abstract)

UV absorbers are sustainable substances that inhibit the ultraviolet (UV) radiative degradation of polymers.
In previous reports, the as-prepared carbon dots (CDs) possess only an absorption band at UVA(320–400 nm). To achieve broad-spectrum UV absorption (200–400 nm), increasing the concentrationof the CDs solution becomes common. However, a high concentration solution seriously affects the lighttransmittance due to its heavy yellow color. Furthermore, the promising organic UV absorbers cannotachieve broad-spectrum UV absorption. In this work, we initially synthesized three-component watersolublecarbon dots (OP–CDs), which delivers an excellent UV absorption (98 % UVA and 100 % UVB atthe concentration of 1.7 102 mg/mL; 99 % transmittance in visible light). Moreover, OP–CDs exhibitoutstanding stability at high temperatures and different pH. With the corporation of OP–CDs and polyvinylalcohol (PVA), a high-performance UV-shielding film was formed, leading to enhanced broadspectrumUV shielding performance and improved mechanical properties, resistance of photocatalyticactivity and anti-UV aging ability compared with pure PVA film. Notably, the PVA film remains hightransparency with the addition of OP–CDs. The study suggests that the corporation of OP–CDs and polymersis effective in anti-UV degradation.