磷酸根和Nafion修饰TiO<sub>2</sub>表面腐植酸调控的可见光催化降解苯酚性能

引用本文: 郑龙辉, 于晓娟, 龙明策, 李琪琳. 磷酸根和Nafion修饰TiO₂表面腐植酸调控的可见光催化降解苯酚性能[J]. 催化学报, 2017, 38(12): 2076-2084. doi: 10.1016/S1872-2067(17)62951-6 shu

Citation: Longhui Zheng, Xiaojuan Yu, Mingce Long, Qilin Li. Humic acid-mediated visible-light degradation of phenol on phosphate-modified and Nafion-modified TiO₂ surfaces[J]. Chinese Journal of Catalysis, 2017, 38(12): 2076-2084. doi: 10.1016/S1872-2067(17)62951-6 shu

磷酸根和Nafion修饰TiO₂表面腐植酸调控的可见光催化降解苯酚性能

a 上海交通大学环境科学与工程学院, 上海 200240, 中国;
b 上海交通大学薄膜与微细技术教育部重点实验室, 上海 200240, 中国;
c 莱斯大学土木与环境工程系, 德克萨斯休斯敦 77005, 美国
基金项目:
国家自然科学基金（21377084）；农业部公益性行业专项（201503107）；上海市国际合作基金（15230724600）.

摘要: 光催化水处理技术有望成为一种有效去除水中难降解有机污染物的方法.尽管人们已经研制了大量的新型光催化剂，但在环境应用中纳米TiO₂仍是最受欢迎的催化剂.由于光催化反应在表面发生，反应动力学主要取决于TiO₂的表面性质，因此，表面修饰是调控TiO₂光催化反应的重要手段，其中Nafion和磷酸根表面修饰TiO₂简单可行.Nafion修饰可以通过离子交换吸附富集阳离子底物提高光催化降解效率；而磷酸根修饰则可以增强对弱吸附底物的降解活性.另一方面，水中共存的天然有机物（NOM）例如腐植酸（HA）将抑制TiO₂光催化降解目标污染物的活性，同时又将通过光敏化诱导可见光催化性能.因此，研究如何调控NOM对光催化反应的影响将有助于光催化水处理技术的工程应用.本文以HA作为代表性的NOM，研究了磷酸根和Nafion两种不同修饰方法对HA敏化TiO₂性能的影响规律.
可见光降解苯酚的实验结果表明，HA的敏化可以提高TiO₂可见光降解苯酚的效率.磷酸根修饰TiO₂抑制了HA的敏化作用，而Nafion修饰则增强了HA的敏化作用并提高可见光降解苯酚的活性.当HA浓度为20 mg/L时，Nafion修饰TiO₂降解10 mg/L苯酚的反应速率常数由（0.003±0.001）min^-1提高至（0.025±0.003）min^-1.表面修饰引起的反应活性差异不能归因于HA的吸附容量的变化，因为吸附实验表明在光催化反应条件下，两种表面修饰的TiO₂对HA的吸附容量并无显著差异.添加不同的自由基捕获剂发现，HA敏化TiO₂及Nafion修饰TiO₂降解苯酚的主要活性物质为超氧自由基，而磷酸根修饰TiO₂的光催化反应中并没有超氧自由基.通过检测超氧自由基的电子自旋共振信号进一步证实了这一点.测试发现，光催化反应中Nafion修饰TiO₂产生的H₂O₂增加，而磷酸根修饰的几乎不产生H₂O₂，说明可能发生了四电子的氧还原反应.莫特-肖特基曲线（Mott-Schottky）的测试结果表明，Nafion修饰TiO₂的平带电位从-0.54 V负移到-0.85 V，多数载流子电子的密度提高了62%.电化学阻抗结果显示，Nafion修饰TiO₂具有较小的界面电子迁移阻抗.这些变化有利于提高电子迁移速率，抑制复合并增加超氧自由基的生成，从而提高光催化性能.因此对TiO₂进行恰当的表面修饰，将有助于强化HA的敏化作用，并提高可见光催化降解目标有机污染物的活性.

关键词:

English

Humic acid-mediated visible-light degradation of phenol on phosphate-modified and Nafion-modified TiO₂ surfaces

a School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China;
b Key Laboratory for Thin Film and Microfabrication of the Ministry of Education, Shanghai Jiao Tong University, Shanghai 200240, China;
c Department of Civil and Environmental Engineering, Rice University, Houston, Texas 77005, United States
Received Date: 09 October 2017
Revised Date: 30 October 2017
Fund Project:
This work was supported by the National Natural Science Foundation of China (21377084), Special Fund for Agro-Scientific Research in the Public Interest (201503107), and Shanghai Municipal International Cooperation Foundation (15230724600).

Abstract: Although humic acid (HA) can inhibit TiO₂ photocatalysis, it can sensitize TiO₂ and induce significant visible-light (VL) activity in phenol degradation. This favorable effect of HA was negligible on phosphate-modified TiO₂ (P-TiO₂), but significantly stronger on Nafion-modified TiO₂ (Nf-TiO₂). The reaction rate constants for phenol degradation on Nf-TiO₂ increased from (0.003±0.001) to (0.025±0.003) min^-1 when the reaction was performed in the presence of 20 mg/L HA. The different effects of HA on P-TiO₂ and Nf-TiO₂ photocatalysis cannot be attributed to adsorption changes, because the adsorption capacities of P-TiO₂ and Nf-TiO₂ were only slightly lower than that of TiO₂ at an initial HA concentration of 20 mg/mL. Scavenger tests, electron paramagnetic resonance spectroscopy, and H₂O₂ detection were taken to understand the low VL activity of the P-TiO₂/HA suspension. The main active species for phenol degradation in the TiO₂ and Nf-TiO₂ suspensions were superoxide radicals. There were negligible amounts of superoxide radicals in the P-TiO₂/HA suspension, possibly because a direct four-electron oxygen reduction reaction occurred. The better VL activity of Nf-TiO₂ was rationalized on the basis of Mott-Schottky and electrochemical impedance plots. Nafion modification resulted in cathodic shifts of the energy band positions, increased electron density, and less resistance to electron transfer across the interface between TiO₂ and electrolytes. All these factors facilitated electron transfer and improved the production of active species. Phosphate modification therefore did not improve the VL response of HA sensitized TiO₂, and low concentrations of HA can facilitate VL photocatalytic degradation of organic pollutants on Nafion surface-modified TiO₂.

Key words:

1. [1] U. I. Gaya, A. H. Abdullah, J. Photochem. Photobiol. C, 2008, 9, 1-12.
2. [2] X. H. Guan, J. S. Du, X. G. Meng, Y. K. Sun, B. Sun, Q. H. Hu, J. Hazard. Mater., 2012, 215-216, 1-16.
3. [3] H. R. Dong, G. M. Zeng, L. Tang, C. Fan, C. Z. Zhang, X. X. He, Y. He, Water Res., 2015, 79, 128-146.
4. [4] M. C. Wen, S. S. Zhang, W. R. Dai, G. S. Li, D. Q. Zhang, Chin. J. Catal., 2015, 36, 2095-2102.
5. [5] Y. Du, D. D. Tang, G. K. Zhang, X. Y. Wu, Chin. J. Catal., 2015, 36, 2219-2228.
6. [6] X. F. Wang, R. Yu, K. Wang, G. Q. Yang, H. G. Yu, Chin. J. Catal., 2015, 36, 2211-2218.
7. [7] M. C. Long, L. H. Zheng, Chin. J. Catal., 2017, 38, 617-624.
8. [8] M. C. Long, W. M. Cai, Nanoscale, 2014, 6, 7730-7742.
9. [9] J. X. Low, J. G. Yu, M. Jaroniec, S. Wageh, A. A. Al-Ghamdi, Adv. Mater., 2017, 29, 1601694.
10. [10] M. S. Akple, J. X. Low, Z. Y. Qin, S. Wageh, A. A. Al-Ghamdi, J. G. Yu, S. W. Liu, Chin. J. Catal., 2015, 36, 2127-2134.
11. [11] Y. F. Li, W. P. Zhang, X. Shen, P. F. Peng, L. B. Xiong, Y. Yu, Chin. J. Catal., 2015, 36, 2229-2236.
12. [12] Y. K. Ooi, L. Yuliati, S. L. Lee, Chin. J. Catal., 2016, 37, 1871-1881.
13. [13] C. L. Zhang, H. Hua, J. L. Liu, X. Y. Han, Q. P. Liu, Z. D. Wei, C. B. Shao, C. G. Hu, Nano-Micro Lett., 2017, 9, 49-61.
14. [14] E. L. Cates, Environ. Sci. Technol., 2017, 51, 757-758.
15. [15] C. P. Sajan, S. Wageh, A. A. Al-Ghamdi, J. G. Yu, S. W. Cao, Nano Res., 2016, 9, 3-27.
16. [16] H. Park, Y. Park, W. Kim, W. Choi, J. Photochem. Photobio. C, 2013, 15, 1-20.
17. [17] M. Long, L. Zheng, B. Tan, H. Shu, Appl. Surf. Sci., 2016, 386, 434-441.
18. [18] S. G. Kumar, K. S. R. K. Rao, Appl. Surf. Sci., 2017, 391, 124-148.
19. [19] J. X. Low, B. Cheng, J. G. Yu, Appl. Surf. Sci., 2017, 392, 658-686.
20. [20] J. Wen, X. Li, W. Liu, Y. Fang, J. Xie, Y. Xu, Chin. J. Catal., 2015, 36, 2049-2070.
21. [21] L. Q. Jing, Y. Cao, H. Q. Cui, J. R. Durrant, J. W. Tang, D. N. Liu, H. G. Fu, Chem. Commun., 2012, 48, 10775-10777.
22. [22] K. Pan, Z. Y. Liu, J. Q. Hu, J. Li, Z. H. Li, D. Li, Y. Liu, M. Liu, J. H. Li, D. J. Wang, Y. B. Yu, T. J. Li, Chem. Res. Chin. Univ., 2005, 21, 360-364.
23. [23] Z. Long, G. R. Deng, C. P. Liu, J. J. Ge, W. Xing, S. H. Ma, Chin. J. Catal., 2016, 37, 988-993.
24. [24] J. Park, J. Yi, T. Tachikawa, T. Majima, W. J. Choi, J. Phys. Chem. Lett., 2010, 1, 1351-1355.
25. [25] X. L. Zheng, J. P. Song, T. Ling, Z. P. Hu, P. F. Yin, K. Davey, X. W. Du, S. Z. Qiao, Adv. Mater., 2016, 28, 4935-4942.
26. [26] W. Y. Wang, Y. Ku, Colloids Surf. A, 2007, 302, 261-268.
27. [27] M. S. Vohra, K. Tanaka, Environ. Sci. Technol., 2001, 35, 411-415.
28. [28] K. T. Chen, C. S. Lu, T. H. Chang, Y. Y. Lai, T. H. Chang, C. W. Wu, C. C. Chen, J. Hazard. Mater., 2010, 174, 598-609.
29. [29] V. Arun, K. R. Sankaran, J. Electroanal. Chem., 2016, 769, 35-41.
30. [30] H. Park, W. Choi, J. Phys. Chem. B, 2005, 109, 11667-11674.
31. [31] H. Sheng, Q. Li, W. H. Ma, H. W. Ji, C. C. Chen, J. C. Zhao, Appl. Catal. B, 2013, 138-139, 212-218.
32. [32] M. Long, J. Brame, F. Qin, J. Bao, Q. Li, P. J. Alvarez, Environ. Sci. Technol., 2017, 51, 514-521.
33. [33] D. Zhao, C. C. Chen, Y. F. Wang, H. W. Ji, W. H. Ma, L. Zang, J. C. Zhao, J. Phys. Chem. C, 2008, 112, 5993-6001.
34. [34] Y. Cao, L. Q. Jing, X. Shi, Y. B. Luan, J. R. Durrant, J. W. Tang, H. G. Fu, Phys. Chem. Chem. Phys., 2012, 14, 8530-8536.
35. [35] C. Liu, F. Raziq, Z. J. Li, Y. Qu, A. Zada, L. Q. Jing, Chin. J. Catal., 2017, 38, 1072-1078.
36. [36] J. Brame, M. C. Long, Q. Li, P. Alvarez, Water Res., 2015, 84, 362-371.
37. [37] J. Brame, M. C. Long, Q. Li, P. Alvarez, Water Res., 2014, 60, 259-266.
38. [38] Y. Lee, U. von Gunten, Water Res., 2010, 44, 555-566.
39. [39] T. E. Doll, F. H. Frimmel, Water Res., 2005, 39, 403-411.
40. [40] M. Fujii, E. Otani, Water Res., 2017, 123, 642-654.
41. [41] S. Li, J. Y. Hu, J. Hazard. Mater., 2016, 318,134-144.
42. [42] A. Pajares, M. Bregliani, J. Natera, S. Criado, S. Miskoski, J. P. Escalada, N. A. García, J. Photochem. Photobiol. A, 2011, 219, 84-89.
43. [43] Y. Li, J. F. Niu, E. X. Shang, J. C. Crittenden, Water Res., 2016, 98, 9-18.
44. [44] Y. Chen, K. Zhang, Y. G. Zuo, Sci. Total Environ., 2013, 463-464, 802-809.
45. [45] P. Calza, D. Vione, C. Minero, Sci. Total Environ., 2014, 493, 411-418.
46. [46] E. Lee, C. M. Glover, F. L. Rosario-Ortiz, Environ. Sci. Technol., 2013, 47, 12073-12080.
47. [47] K. Vinodgopal, P. V. Kamat, Environ. Sci. Technol., 1992, 26, 1963-1966.
48. [48] C. S. Uyguner, M. Bekbolet, Catal. Today, 2005, 101, 267-274.
49. [49] C. Wang, M. C. Long, B. H. Tan, L. H. Zheng, J. Cai, J. J. Fu, Electro-chim. Acta, 2017, 250, 108-116.
50. [50] H. Bader, V. Sturzenegger, J. Hoigné, Water Res., 1988, 22, 1109-1115.
51. [51] H. T. Liu, H. Gao, M. C. Long, H. Y. Fu, P. J. J. Alvarez, Q. L. Li, S. R. Zheng, X. L. Qu, D. Q. Zhu, Environ. Sci. Technol., 2017, 51, 6877-6886.
52. [52] S. Kim, W. Choi, J. Phys. Chem. B, 2005, 109, 5143-5149.
53. [53] B. H. Gu, J. Schmitt, Z. H. Chen, L. Y. Liang, J. F. McCarthy, Environ. Sci. Technol., 1994, 28, 38-46.
54. [54] S. H. Kang, B. S. Xing, Langmuir, 2008, 24, 2525-2531.
55. [55] H. Sheng, H. W. Ji, W. H. Ma, C. C. Chen, J. C. Zhao, Angew. Chem. Int. Ed., 2013, 52, 9686-9690.

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沈阳化工大学材料科学与工程学院沈阳 110142

磷酸根和Nafion修饰TiO₂表面腐植酸调控的可见光催化降解苯酚性能

English

Humic acid-mediated visible-light degradation of phenol on phosphate-modified and Nafion-modified TiO₂ surfaces

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中国化学会秘书处

磷酸根和Nafion修饰TiO2表面腐植酸调控的可见光催化降解苯酚性能

English

Humic acid-mediated visible-light degradation of phenol on phosphate-modified and Nafion-modified TiO2 surfaces

CCS Chemistry：嵌段共聚物自组装成 “三明治”二维有机材料，实现纳米级压力传感功能

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通讯作者: 陈斌, bchen63@163.com

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磷酸根和Nafion修饰TiO₂表面腐植酸调控的可见光催化降解苯酚性能

Humic acid-mediated visible-light degradation of phenol on phosphate-modified and Nafion-modified TiO₂ surfaces

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