Synthesis of Porous Boron-Doped Carbon Nitride: Adsorption Capacity and Photo-Regeneration Properties

• Main Authors: Xiang Guo, Lei Rao, Peifang Wang, Lixin Zhang, Yuxiong Wang
• Format: Article
• Language: English
• Published: MDPI AG 2019-02-01
• Series: International Journal of Environmental Research and Public Health
• Subjects: adsorption; photocatalytic; regenerate; carbon nitride; B₂O₃
• Online Access: https://www.mdpi.com/1660-4601/16/4/581

Carbon nitride (CN) with improved adsorption⁻degradation capacity was synthesized using B₂O₃ and CN via calcination. The pollutant removal capacity of this B₂O₃/CN (B-CN) was studied by a powder suspension experiment and added into concrete to evaluate the adsorption and degradation of methylene blue (MB). The characterizations of all samples indicate that B₂O₃ significantly affects CN, e.g., by increasing the CN specific surface area to 3.6 times the original value, extending visible light adsorption, and narrowing the band gap from 2.56 eV to 2.42 eV. Furthermore, the results show that B-CN composite materials have a higher MB-removal efficiency, with the adsorption capacity reaching 43.11 mg/g, which is about 3.3 times that of pristine CN. The MB adsorption process on B2-CN is mainly via electrostatic attraction and π⁻π interactions. In addition, B-CN added into concrete also has good performance. After five adsorption⁻degradation cycles, B-CN and photocatalytic concrete still exhibit a good regenerate ability and excellent stability, which are very important for practical applications.