共聚改性g-C<sub>3</sub>N<sub>4</sub>-N可见光催化降解RhB的研究

doi:10.3964/j.issn.1000-0593(2021)02-0517-06

摘要
参考文献
相关文章 (15)

全文: PDF (2657 KB)
输出: BibTeX | EndNote (RIS)

摘要：染料废水的排放对人类健康和生态系统构成严重威胁，光催化技术因其操作简单、绿色环保等优点在解决环境污染问题上已显示出巨大的潜力。类石墨相氮化碳（g-C₃N₄）由于成本低且具有良好的化学稳定性，被认为是光催化领域最有前景的新型光催化剂之一，但由于单一g-C₃N₄的比表面积小、可见光吸收能力低、光生电子-空穴复合率高影响了其光催化性能。以邻氨基苯甲腈和尿素为原料，通过高温共聚改性制备高催化活性的g-C₃N₄-N光催化剂，研究g-C₃N₄-N在不同pH值、g-C₃N₄-N投加量和RhB溶液浓度条件下对RhB光催化降解的影响，并结合红外光谱、XRD、BET、UV-Vis对g-C₃N₄-N光催化降解RhB的机理和染料降解路径进行解析。结果表明，经共聚改性制备的碳化氮为类石墨型纯相g-C₃N₄-N，具有稳定的光催化活性、大的比表面积和多孔结构，在初始pH值为3时，加入50 mg的g-C₃N₄-N在可见光条件下光催化降解10 mg·L^-1 的RhB可达到最好的光催化降解效果，RhB在暗反应30 min内的吸附去除率可达30%左右，120 min的去除率达到97.7%。在光催化作用下，g-C₃N₄-N将吸附在光催化剂表面的罗丹明B分子通过快速N-脱乙基过程形成DER、EER和AR等大分子中间体，它们在空穴与·OH和·O^-₂作用下，共轭结构裂解、开环，生成丁二酸、间苯二酚、丙酸等小分子，脱除的乙基被逐步氧化为乙二醇，这些小分子可以被转化为CO₂和H₂O。

关键词：可见光；催化降解；罗丹明B；g-C₃N₄-N；共聚合改性；FTIR；UV-Vis

Abstract：The discharge of dye wastewater has become a serious threat to human health and the ecosystem. Photocatalytic technology has shown attractive potential in eliminating environmental pollution problems owing to its simple operation and environment-friendly. Graphite-like phase carbon nitride (g-C₃N₄) was considered to be one of the most promising photocatalysts for its low cost and high chemical stability in the field of photocatalysis. However, poor specific surface area, limited optical absorption and high charge carrier recombination rate restricted its photocatalytic efficiency. Thus, a novel graphitic carbon nitride(g-C₃N₄-N) photocatalyst was synthesized by thermos-induced copolymerization modification method using urea and o-Aminobenzontrile, and its effect on photocatalytic degradation ability of RhB was evaluated based on solution pH value, g-C₃N₄-N dosage, and RhB concentration. In addition, both the photocatalytic degradation mechanism of RhB and its degradation path by g-C₃N₄-N were also analyzed through XRD, BET, UV-Vis in this research. The results showed that g-C₃N₄-N synthesized using copolymerization modification method was pure graphite-like phase g-C₃N₄-N, with the stable performance of a photocatalytic activity, large specific surface area and porous structure. Under visible light conditions, the photocatalytic degradation efficiency of RhB was found to be optimal with initial pH of 3, RhB concentration of 10 mg·L^-1 and g-C₃N₄-N dosage of 50 mg, and the adsorption removal rate of RhB was achieved 30% within 30 minutes in dark reaction. Besides, its photocatalytic degradation removal rate of 120 minutes reach 97.7%. Under the catalysis of visible light, RhB molecules adsorbed on the surface of the g-C₃N₄-N was firstly degraded into macromolecular intermediates such as DER, EER and AR through rapid N-de-ethylation process, then base on redox reaction of holes, ·OH and ·O^-₂, conjugated structure of these intermediates was cracked and ring-opened to generate some small molecules, such as succinic acid, resorcinol, and propionic acid, and so on. After that, the removed ethyl groups were gradually oxidized to ethylene glycol. And these small molecules were eventually mineralized into CO₂ and H₂O.

Key words：Visible-light; Catalytic degradation; RhB; g-C₃N₄-N; Copolymerization modification; FTIR; UV-Vis

收稿日期: 2020-09-16 修订日期: 2020-11-09

中图分类号:

TQ426.7

基金资助: 国家自然科学基金项目（51306155），中央高校基本科研业务费重点项目（XDJK2017B059）资助

通讯作者: 潘云霞 E-mail: panyx@swu.edu.cn

作者简介: 夏雪，女，1996年生，西南大学工程技术学院硕士研究生 e-mail：yuki5607@email.swu.edu.cn

引用本文:

夏雪，潘云霞，李梦祝. 共聚改性g-C₃N₄-N可见光催化降解RhB的研究[J]. 光谱学与光谱分析, 2021, 41(02): 517-522.
XIA Xue, PAN Yun-xia, LI Meng-zhu. Photocatalytic Degradation of RhB Dye by Copolymerization Modification g-C₃N₄-N Under Visible Light. SPECTROSCOPY AND SPECTRAL ANALYSIS, 2021, 41(02): 517-522.

链接本文:

https://www.gpxygpfx.com/CN/10.3964/j.issn.1000-0593(2021)02-0517-06 或 https://www.gpxygpfx.com/CN/Y2021/V41/I02/517

[1] ZHAO Zi-shi, WANG Dong-liang, WANG Tao, et al（赵子石，王栋良，王騊，等）. Journal of Zhejiang Sci-Tech University·Natural Sciences Edition（浙江理工大学学报·自然科学版），2010，27（5）：693.
[2] Goncalves M S T, Oliveira-Campos A M F, Pinto E, et al. Chemosphere，1999，39（5）：781.
[3] Yan S C, Zou Z G, Li Z S. Langmuir，2009，25（17）：10397.
[4] Dong F, Wu L W, Sun Y J, et al. Journal of Materials Chemistry，2011，21（39）：15171.
[5] Ji H H, Chang F, Hu X F, et al. Chemical Engineering Journal，2013，218：183.
[6] CHENG Hong-fei, DU Bei-bei, SUN Zhi-ming, et al（程宏飞，杜贝贝，孙志明，等）. Bulletin of the Chinese Ceramic Society（硅酸盐通报），2017，36（12）：4229.
[7] ZHENG Hua-rong, ZHANG Jin-shui, WANG Xin-chen, et al（郑华荣，张金水，王心晨，等）. Acta Physico-Chimica Sinica（物理化学学报），2012，28（10）：2336.
[8] Shakeel M, Arif M, Yasin G, et al. Applied Catalysis B: Environmental，2019，242：485.
[9] Lin Q C, Li Z S, Lin T J, et al. Chinese Journal of Chemical Engineering，2020, 28(10): 2677.
[10] LI Xiang-yu, LI Xue-qin, LI A-liang, et al（李翔宇，李学琴，李阿良，等）. Journal of Beihua University·Natural Science（北华大学学报·自然科学版），2019，20（5）：572.
[11] Zhang Q J, Wu Y F, Yuan H R. Resources, Conservation and Recycling，2020，161：104983.
[12] Acharya R, Parida K. Journal of Environmental Chemical Engineering，2020，8（4）：103896.
[13] He F, Wang Z X, Li Y X, et al. Applied Catalysis B: Environmental，2020，269：118828.
[14] Chang S Y, Harle G, Ma J L, et al. Applied Catalysis A: General，2020，604：117775.
[15] ZHU Yu-xin, OUYANG Jie, SONG Yan-hua, et al（祝玉鑫，欧阳杰，宋艳华，等）. Chemical Journal of Chinese Universities（高等学校化学学报），2020，41（7）：1645.
[16] Liao Y L, Zhu S M, Chen Z X, et al. Physical Chemistry Chemical Physics，2015，17（41）：27826.
[17] Luo H D, Guo J X, Shen T, et al. Journal of the Taiwan Institute of Chemical Engineers，2020，109：15.
[18] Hasanpour M，Hatami M. Journal of Molecular Liquids，2020，309：113094.
[19] Ganguly P, Panneri S, Hareesh U S, et al. Nanoscale Materials in Water Purification，2019，653.
[20] Belver C, Bedia J, Gómez-Avilés A, et al. Nanoscale Materials in Water Purification，2019，581.