Organic Dye Degradation with High Reusability
Environmental problems have escalated in recent years. The urgent need to enact stringent measures to combat environmental pollution can be attributed to the prevailing campaigns and increased awareness of its impacts. Water pollution resulting from the discharge of organic dye into the aqueous environment has caused severe environmental problems. Considering that organic dye, especially rhodamine, is difficult to degrade, effective removal methods have been researched. Among them, the photocatalysis technique, which exhibits high potential use in wastewater treatment, have been employed. Consequently, TiO2 has been identified as a promising photocatalyst owing to its excellent chemical stability, redox reactivity, and low-cost properties. Despite TiO2 having a wide range of applications, its application has remained underexplored due to its inability to absorb and use visible light.
In order to broaden the light absorption of TiO2 to visible light, researchers at Nanchang Hangkong University: Pingping Niu (Master Student), Professor Guanghui Wu, Dr. Pinghua Chen, Huitao Zheng (Master Student), Professor Qun Cao, and Professor Hualin Jiang prepared several boron-doped TiO2 materials, using facile co-precipitation and calcination processes, for use as photocatalyst in organic dye degradation under visible light. Their work is currently published in the research journal, Frontiers in Chemistry.
The authors commenced their experimental work by preparing the B-TiO2 photocatalysts by doping boron into TiO2. Next, they investigated its photocatalytic degradation ability towards rhodamine B under visible light. In their work, they also evaluated the structure and photocatalytic performance of B-TiO2 photocatalyst by optimizing the preparation conditions.
Results showed that B-TiO2 exhibited high photocatalytic degradation ability toward rhodamine B in the presence of visible light. Boron doping narrowed the bandgap of TiO2 to broaden adsorption to visible light. The boron-doped materials, however, exhibited the highest activity when the mass fraction of boron was 6%, otherwise referred to as 6B-TiO2. On the other hand, a comparison between the bare TiO2 and boron-doped TiO2, considering photogenerated electron-hole pairs, generation abilities of the photoinduced electrons, and the transferring speed of the photoinduced charges, identified the role of h+ and O–2 species as the main active species behind the high photocatalytic oxidation process. Additionally, it was worth noting that 6B-TiO2 could be reused in the photocatalysis process without significant reduction in the activity. Thus, 6B-TiO2 was identified as the optimal boron doping amount.
In summary, Nanchang Hangkong University scientists successfully prepared a photocatalyst of B-TiO2 by doping boron into TiO2. Based on the results, 6B-TiO2 exhibited enhanced photocatalytic performance and was identified as the optimal boron doping amount. Furthermore, its reusability of up to five cycles means that it is environmentally friendly and cost-effective. In a statement to Advances in Engineering, Professor Hualin Jiang pointed out that 6B-TiO2 is a potential photocatalyst for alleviating dye-related pollution.
Niu, P., Wu, G., Chen, P., Zheng, H., Cao, Q., & Jiang, H. (2020). Optimization of Boron Doped TiO2 as an Efficient Visible Light-Driven Photocatalyst for Organic Dye Degradation with High Reusability. Frontiers in Chemistry, 8.