Controllable Synthesis of Carbon DotCaco3 Composites : Tunable Morphology, Uv Absorption Properties, and Application as Ultraviolet Absorber

Ultraviolet (UV) absorbers can reduce the damage of UV irradiation to materials and effectively delay the life of polymers, whereas commercial inorganic UV absorbers tend to generate free radicals that accelerate the breakdown of materials. This work proposes carbon dot (CD) with UV absorbing properties to mineralize CaCO 3 to different degrees to prepare excellent UV absorbers. CD with -3.77 mV negative charge and rich in functional groups such as -COOH, -OH, -NH 2 and -C=O were synthesized using one-step method to induce typical rhombic CaCO 3 to form other irregular morphologies, including polycrystalline rhombic, fancy spheres, polycrystalline fancy spheres and smooth spheres. Not only that, the UV absorption property of CD endows CaCO 3 a strong UV absorption property at 200-400 nm. Also, it is proposed that the stability of the complexes is higher than that of pure CD. The complexes have excellent dispersibility,, optical stability, high-temperature resistance, and anti-aging property of CaCO 3 . Finally, in order to reflect the practical application of CD@CaCO 3 , it's compounded with the polymer material PU, which increases the UV resistance and mechanical properties of PU film, and the application of light conversion film has great potential value in agriculture. There is a great prospect of modified CaCO 3 by taking advantage of the CD as the UV absorber