Visible Light Enhancement of Biocarbon Quantum-Dot-Decorated TiO2 for Naphthalene Removal

• Published in: Molecules (Basel, Switzerland) Vol. 29; no. 11; p. 2708
• Main Authors: Chen, Yunteng, Hong, Chunxian, Xu, Qiang, Zheng, Haihong, Wang, Chao, Lu, Hongshun, Zhang, Shuai, Du, Mingming, Zeng, Ganning
• Format: Journal Article
• Language: English
• Published: Basel MDPI AG 06.06.2024; MDPI
• Subjects: Algae; Biomass; Carbon; carbon quantum dots; Cellulose; Composite materials; Efficiency; Electrons; Free radicals; Light; naphthalene; Photocatalysis; photodegradation; Quantum dots; TiO2; Ultraviolet radiation
• ISSN: 1420-3049; 1420-3049
• DOI: 10.3390/molecules29112708

In this study, carbon-quantum-dot (CQD)-decorated TiO2 was prepared using an ultrasonic doping method and applied in the photocatalytic degradation of naphthalene under sunlight irradiation. The CQDs were synthesized from a typical macroalgae via diluted sulfuric acid pretreatment and hydrothermal synthesis using an optimal design, i.e., 3 wt% and 200 °C, respectively. The CQD/TiO2 composite remarkably enhanced the photocatalytic activity. The degradation of naphthalene under a visible light environment indicated that there is a synergistic mechanism between the CQDs and TiO2, in which the generation of reactive oxygen species is significantly triggered; in addition, the N that originated from the macroalgae accelerated the photocatalytic efficiency. Kinetic analysis showed that the photocatalytic behavior of the CQD/TiO2 composite followed a pseudo-first-order equation. Consequently, our combined experimental approach not only provides a facile pretreatment process for bio-CQDs synthesis, but also delivers a suitable TiO2 photocatalyst for the visible environment along with critical insights into the development of harmful macroalgae resources.