High efficiency of CQDs/UiO-66 photocatalytic nanocomposite for degradation of RR-195 under visible irradiation

CQDs, characteristically quasispheroidal carbon nanoparticles composed of amorphous to crystalline carbon base,  are a prospective semiconductor quantum dots owing to its excellent optical absorptivity, chemical stability, nontoxicity, and facile synthesis. In this study, we demonstrated the impregnation method to integrate CQDs, formed from chitosan with UiO-66 from terephthalic acid recycled by waste PET to synthesize CQDs@UiO-66 nanocomposite. After the hybridization of CQDs with UiO-66, the low band gap energy of the CQDs@UiO-66 sample was determined at 2.4 eV, allowed the demonstration of photocatalytic activity under high visible light. This material was tested in the photodegradation of RR-195 dye and compared with the pristine components. The highest RR-195 degradation efficiency recorded when using the catalyst mass of 50 mg, dye concentration of 70 ppm after 4 h under visible light irradiation was 96% and the result rather maintained its performance (86,4%) after four cycles. These results could promote a new material circularity pathway to develop new semiconductors that can be used to protect water from further pollution.