Synthesis of efficient broad-spectrum UV-absorbing carbon dots as UV absorbers using natural rutin as raw material and their multifunctional applications under acid-base amphoteric conditions

In this paper, a kind of novel fully UV absorbing carbon dots (R-CDs) were prepared as UV absorbers by a one-step hydrothermal method using natural renewable rutin as raw material. R-CDs can achieve multifunctional applications under acid-base amphoteric conditions. Under acidic conditions, R-CDs have high absorption efficiency (over 98%) in the whole ultraviolet region (200–400 nm) which have wider UV absorption range than commercial water-soluble organic UV absorbers (BP-4) and are almost completely transmitted in the visible light region. The UV absorption mechanism of R-CDs be investigated to the UV absorption systems of degradable cellulose coating (CMC) and the R-CDs@CMC coating was applied to prevent UV leakage of the 395UV chip. Under alkaline conditions, R-CDs remain fully UV absorbing and good absorption stability, but BP-4 loses its function as a UV absorber. Finally, R-CDs was applied to the UV absorption and anti-blue light systems of PU. The R-CDs@PU are more effective than commercially available anti-blue light lenses. At present, the preparation process of R-CDs is simple and rutin is a natural renewable energy source. So, R-CDs have the potential to become a new generation of water-soluble UV absorbers and be applied to prevent blue light.