抑制阳极钝化与提升效率: 乙醇在苯酚电氧化制对苯醌中的作用机制

doi:10.6023/cjoc202512037

摘要/Abstract

针对苯酚电化学氧化过程中阳极钝化严重、目标产物选择性低的关键问题, 以铂电极为工作电极, 通过引入乙醇作为添加剂, 探究乙醇对阳极钝化的抑制机制及对苯酚电氧化效率的提升作用. 气质联用(GC-MS)和傅里叶变换红外光谱(FTIR)测试结果表明, 钝化层由苯酚氧化中间体聚合形成. 电解结果表明, 乙醇可促进苯酚向对苯醌的选择性转化, 提高苯酚电氧化效率. 结合对苯二酚的线性扫描伏安曲线和铂电极接触角测试, 推测乙醇可加速产物对苯醌的脱附过程, 减缓苯酚氧化中间体聚合, 进而抑制电极表面形成钝化层, 最终加速苯酚向对苯醌选择性氧化. 在5 mmol/L苯酚、通电量25 F/mol、电流密度25 mA/cm²、温度25 ℃的条件下, 当电解液中添加0.51 mol/L乙醇后, 苯酚转化率、对苯醌收率及选择性分别提高了23.5%、34.1%和26.2%. 此研究证实乙醇可有效抑制阳极钝化, 显著促进苯酚转化为对苯醌, 为对苯醌的电化学合成工艺优化及阳极抗钝化设计提供了实验与理论支撑.

关键词: 苯酚电氧化, 阳极钝化, 乙醇添加剂, Pt电极

To address the critical issues of severe anodic passivation and low selectivity of target products during the electrochemical oxidation of phenol, this study adopted a platinum electrode as the working electrode and introduced ethanol as an additive to investigate the inhibition effect of ethanol on anodic passivation and its promoting effect on the electro- oxidation efficiency of phenol. Results from gas chromatography-mass spectrometry (GC-MS) and Fourier transform infrared spectroscopy (FTIR) analyses indicated that the passivation layer is formed by the polymerization of phenol oxidation intermediates. The electrolysis results indicated that ethanol can promote the selective conversion of phenol to p-benzoquinone (p-BQ), thereby enhancing the efficiency of phenol electrooxidation. Combined with the LSV curves of hydroquinone and the contact angle measurements of the platinum electrode, it is inferred that ethanol can accelerate the desorption of p-BQ, thereby slowing down the polymerization of phenol oxidation intermediates, further suppressing the formation of the passivation layer on the electrode surface, and ultimately promoting the selective oxidation of phenol to p-BQ. Under the conditions of 5 mmol/L phenol, 25 F/mol, 25 mA/cm² and 25 ℃, the addition of 0.51 mol/L ethanol to the electrolyte increased the conversion of phenol, as well as the yield and selectivity of p-BQ by 23.5%, 34.1% and 26.2%, respectively. This study demonstrates that ethanol can effectively inhibit anodic passivation and significantly promote the directional conversion of phenol to p-BQ, providing experimental and theoretical support for the process optimization of the electrochemical synthesis of p-BQ and the design of passivation-resistant anodes.

Key words: electrooxidation of phenol, anodic passivation, ethanol additive, Pt electrode

引用此文

黄伟猛, 钮东方, 张新胜. 抑制阳极钝化与提升效率: 乙醇在苯酚电氧化制对苯醌中的作用机制[J]. 有机化学, 2026, 46(6): 2450-2457.

Weimeng Huang, Dongfang Niu, Xinsheng Zhang. Inhibiting Anodic Passivation and Enhancing Efficiency: the Effect of Ethanol on the Electrooxidation of Phenol to p-Benzoquinone[J]. Chinese Journal of Organic Chemistry, 2026, 46(6): 2450-2457.

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图/表 8

图1. 乙醇抑制苯酚电氧化的电极钝化与改善反应效率的作用

Figure 1. Effect of ethanol on inhibiting passivation behavior and improving efficiency in phenol electrooxidation

图2. (a)反应前和(b)反应后铂电极的扫描电镜图; (c)钝化与未钝化铂电极在开路电位下的Nyquist图; (d)钝化物的气相色谱-质谱联用图

Figure 2. Scanning electron microscopy images of (a) clean and (b) passivated platinum electrode; (c) Nyquist diagram of passivated and clean platinum electrode at open circuit potential; (d) gas chromatography-mass spectrometry spectrum of the passivation species

图3. (a)未添加和(b)添加乙醇条件下苯酚电氧化后铂电极的傅里叶红外图

Figure 3. Fourier transform infrared spectroscopy of the platinum electrode after phenol electrooxidation under conditions (a) without ethanol and (b) with ethanol

图4. 通电量对(a)苯酚转化率、对苯醌收率和(b)对苯醌的选择性的影响

Figure 4. Effect of charge passed on (a) conversion of phenol, yield of p-BQ, and (b)selectivity of p-BQ

图5. 乙醇浓度对(a)苯酚转化率、对苯醌收率和(b)对苯醌的选择性的影响

Figure 5. Effect of concentration of ethanol on (a) conversion of phenol, yield of p-BQ, and (b) selectivity of p-BQ

图式1. 苯酚氧化生成对苯醌的分步反应路径

Scheme 1. Stepwise reaction pathway for the oxidation of phenol to p-BQ

图6. (a)添加和未添加乙醇条件下对苯二酚的线性扫描伏安曲线; 电解液中(b)未添加和(c)添加乙醇与铂电极表面的接触角测试

Figure 6. (a) Linear sweep voltammetry curves of hydroquinone with and without ethanol; Contact angle measurements of the platinum electrode surface in electrolyte (b) without and (c) with ethanol

图7. 添加和未添加乙醇条件下苯酚电氧化的计时电位曲线

Figure 7. Chronopotentiometric curves of phenol electrooxidation with and without ethanol

参考文献 18

[1]	(a) Li, Z. L.; Feng, Z. Y.; Chen, M.; Song, Y. K.; Dai, Y. C.; Mao, S.; Zhao, H. Y. Water Res. 2025, 273, 122967.
	(b) Liu, F. Q.; Chen, W.; Wang, T.; Zhang, J. C.; Yang, D. Y.; Dai, Y. H.; Liu, G. Z.; Zhou, J.; Wang, S. Y.; Guan, X. H. Angew. Chem. Int. Ed. 2025, 64, e202415438.
	(c) Wu, R. Z.; Meng, Q. L.; Yan, J.; Liu, H. Z.; Zhu, Q. G.; Zheng, L. R.; Zhang, J.; Han, B. X. J. Am. Chem. Soc. 2022, 144, 1556.
[2]	Oka, S. Agric. Biol. Chem. 1962, 26, 387.
[3]	Griffiths, J. In Ullmann's Encyclopedia of Industrial Chemistry, Vol.A3, Eds.: Elvers, B.; Hawkins, S.; Russey, W., Wiley-VCH, Weinheim, 2006, p. 350.
[1]	(a) Cai, Z. Q. S.; Zhang, J. M.; Lin, Z. W.; Zhao, Y. N.; Yang, Q.; Qiu, X. W.; Lin, S. M.; Liu, D. H.; Hu, X. L.; Bai, H. J. J. Mater. Chem. A 2024, 12, 11439.
	(b) Chu, J.; Li, G. F.; Wang, Y. X.; Zhang, X.; Yang, Z. H.; Han, Y.; Cai, T.-T.; Song, Z. P. ACS Appl. Mater. Interfaces 2022, 14, 25566.
[2]	(a) Li, H. G.; Feng, T. X.; Hou, Y. C.; Ren, S. H.; Wu, W. Z. Ind. Eng. Chem. Res. 2024, 63, 5880.
	(b) Rybin, A. G.; Varvarina, E. A.; Zilberman, E. N. Zh. Org. Khim. 1990, 26, 2460.
[3]	(a) Han, L. Y.; Zhang, X. S.; Xu, Y.; Gao, Z. Q.; Guo, H. Y.; Guo, Q. C.; Hu, S. Z. Chin. J. Org. Chem. 2024, 44, 951. (in Chinese)
	(韩璐瑶, 张新胜, 许颖, 郭庆春, 郭红永, 高照群, 胡硕真, 有机化学, 2024, 44, 951.)
	(b) Guo, H.; Niu, D. F.; Hu, S. Z.; Zhang, X. S. J. Electrochem. 2021, 27, 498. (in Chinese)
	(郭浩, 钮东方, 胡硕真, 张新胜, 电化学, 2021, 27, 498.)
	(c) Mao, L.; Niu, D. F.; Hu, S. Z.; Zhang, X. S. J. Electrochem. 2022, 28, 2107061. (in Chinese)
	(毛麟, 钮东方, 胡硕真, 张新胜, 电化学, 2022, 28, 2107061.)
[4]	(a) Liu, J. K.; Kang, M. D.; Huang, K.; Xu, H. G.; Wu, Y. X.; Zhang, X. Y.; Zhu, Y.; Fan, H.; Fang, S. R.; Zhou, Y.; Lian, C.; Liu, P. F.; Yang, H. G. Nat. Commun. 2025, 16, 3458.
	(b) Hao, G. Y.; Zhao, T.; Fang, Q.; Jia, Y. Z.; Li, D.-D.; Zhong, D. Z.; Li, J. P.; Zhao, Q. Green Chem. 2024, 26, 9782.
	(c) Wang, Q.; Wang, Y.; Liu, M.; Chu, G.; Qiu, Y. Chin. J. Chem. 2024, 42, 2249.
[5]	(a) Mao, J.-J; Wang, Y. B.; Zhang, B.; Lou, Y.; Pan, C. S.; Zhu, Y. F.; Zhang, Y. Green Carbon 2024, 2, 45.
	(b) Martínez-Huitle, C. A.; Panizza, M. Curr. Opin. Electrochem. 2018, 11, 62.
[6]	(a) Al-Maznai, H.; Conway, B. E. J. Serb. Chem. Soc. 2001, 66, 765.
	(b) Chatzisymeon, E.; Fierro, S.; Karafyllis, I.; Mantzavinos, D.; Kalogerakis, N.; Katsaounis, A. Catal. Today 2010, 151, 185.
	(c) Gao, G. D.; Vecitis, C. D. Electrochim. Acta 2013, 98, 131.
[7]	Iniesta, J.; Michaud, P. A.; Panizza, M.; Cerisola, G.; Aldaz, A.; Comninellis, C. Electrochim. Acta 2001, 46, 3573.
[8]	Zhang, X.; Zhu, Y. J.; Ahmed, W.; Niu, D. F. ChemistrySelect 2023, 8, e202301617
[9]	Ežerskis, Z.; Jusys, Z. J. Appl. Electrochem. 2001, 31, 1117.
[10]	Liu, X. F.; You, S. J.; Ma, F.; Zhou, H. Front. Environ. Sci. Eng. 2020, 15, 53.
[11]	(a) Gattrell, M.; Kirk, D.In Symposium on Corrosion Protection by Coatings and Surface Modification, Eds.: Fabry, L.; Pahlke, S.; Kotz, L.; Schemmel, E.; Berneike, W., The Electrochemical Society, Pennington, 1993, Vol. 93.
	(b) Iotov, P. I.; Kalcheva, S. V. J. Electroanal. Chem. 1998, 442, 19.
[12]	Li, M. Q.; Ling, C.-C; Zhao, L.; Hu, L. F.; Li, H.; Zhang, L. Z. J. Am. Chem. Soc. 2025, 147, 31165.
[13]	(a) Barışçı S.; Turkay, O.; Öztürk, H.; Şeker, M. G. J. Electrochem. Soc. 2017, 164, E129.
	(b) Sun, J.; Lu, H.; Lin, H.; Du, L.; Huang, W.; Li, H.; Cui, T. Sep. Purif. Technol. 2012, 88, 116.
[14]	Wang, Y.; Compton, R. G. ChemElectroChem 2020, 7, 3508.
[15]	Hossain, M. M.; Aldous, L. Electrochem. Commun. 2016, 69, 32.
[16]	(a) Enache, T. A.; Oliveira-Brett, A. M. J. Electroanal. Chem. 2011, 655, 9.
	(b) Jin, G. P.; Lin, X. Q.; Ding, Y. F. J. Solid State Electrochem. 2006, 10, 987.
	(c) Li, X. Y.; Cui, Y. H.; Feng, Y. J.; Xie, Z. M.; Gu, J. D. Water Res. 2005, 39, 1972.
	(d) Tahar, N. B.; Savall, A. Electrochim. Acta 2009, 55, 465.
[17]	Gindro, K.; Schnee, S.; Righi, D.; Marcourt, L.; Nejad Ebrahimi, S.; Codina, J. M.; Voinesco, F.; Michellod, E.; Wolfender, J.-L.; Queiroz, F. J. Nat. Prod. 2017, 80, 887.
[18]	Fino, D.; Jara, C.; Saracco, G.; Specchia, V.; Spinelli, P. J. Appl. Electrochem. 2005, 35, 405.