ADDITION / CORRECTIONThis article has been corrected. View the notice.

Multilayer Heterojunction Anodes for Saline Wastewater Treatment: Design Strategies and Reactive Species Generation Mechanisms

View Author Information
Linde + Robinson Laboratories California Institute of Technology Pasadena, California 91125, United States
Cite this: Environ. Sci. Technol. 2016, 50, 16, 8780–8787
Publication Date (Web):July 12, 2016
Copyright © 2016 American Chemical Society
Article Views
Read OnlinePDF (3 MB)
Supporting Info (1)»


Multilayer heterojunction SbSn/CoTi/Ir anodes, which consist of Ir0.7Ta0.3O2 bottom layers coated onto a titanium base, Co-TiO2 interlayers, and overcoated discrete Sb-SnO2 islands, were prepared by spray pyrolysis. The Ir0.7Ta0.3O2 bottom layer serves as an Ohmic contact to facilitate electron transfer from semiconductor layers to the Ti base. The Co-TiO2 interlayer and overcoated Sb-SnO2 islands enhance the evolution of reactive chlorine. The surficial Sb-SnO2 islands also serve as the reactive sites for free radical generation. Experiments coupled with computational kinetic simulations show that while ·OH and Cl· are initially produced on the SbSn/CoTi/Ir anode surface, the dominant radical formed in solution is the dichlorine radical anion, Cl2·. The steady-state concentration of reactive radicals is 10 orders of magnitude lower than that of reactive chlorine. The SbSn/CoTi/Ir anode was applied to electrochemically treat human wastewater. These test results show that COD and NH4+ can be removed after 2 h of electrolysis with minimal energy consumption (370 kWh/kg COD and 383 kWh/kg NH4+). Although free radical species contribute to COD removal, anodes designed to enhance reactive chlorine production are more effective than those designed to enhance free radical production.

Supporting Information

Jump To

The Supporting Information is available free of charge on the ACS Publications website at DOI: 10.1021/acs.est.6b00688.

  • Figures provided in Supporting Information include SEM, LSV, and ECSA measurement of anodes, model simulation results, time profiles of ions, the calculation of FC contribution to pollutant removal and energy consumption in wastewater electrolysis. Tables include human wastewater composition and details of the kinetic model (PDF)

Terms & Conditions

Most electronic Supporting Information files are available without a subscription to ACS Web Editions. Such files may be downloaded by article for research use (if there is a public use license linked to the relevant article, that license may permit other uses). Permission may be obtained from ACS for other uses through requests via the RightsLink permission system:

Cited By

This article is cited by 59 publications.

  1. Heng Dong, Weilai Yu, Michael R. Hoffmann. Mixed Metal Oxide Electrodes and the Chlorine Evolution Reaction. The Journal of Physical Chemistry C 2021, 125 (38) , 20745-20761.
  2. Zichen Liu, Gong Zhang, Huachun Lan, Huijuan Liu, Jiuhui Qu. Optimization of a Hierarchical Porous-Structured Reactor to Mitigate Mass Transport Limitations for Efficient Electrocatalytic Ammonia Oxidation through a Three-Electron-Transfer Pathway. Environmental Science & Technology 2021, 55 (18) , 12596-12606.
  3. Yi Zhang, Yang Yang, Shasha Yang, Estefanny Quispe-Cardenas, Michael R. Hoffmann. Application of Heterojunction Ni–Sb–SnO2 Anodes for Electrochemical Water Treatment. ACS ES&T Engineering 2021, 1 (8) , 1236-1245.
  4. Steven Hand, Roland D. Cusick. Electrochemical Disinfection in Water and Wastewater Treatment: Identifying Impacts of Water Quality and Operating Conditions on Performance. Environmental Science & Technology 2021, 55 (6) , 3470-3482.
  5. Siwen Wang, Shasha Yang, Estefanny Quispe, Hannah Yang, Charles Sanfiorenzo, Shane W. Rogers, Kaihang Wang, Yang Yang, Michael R. Hoffmann. Removal of Antibiotic Resistant Bacteria and Genes by UV-Assisted Electrochemical Oxidation on Degenerative TiO2 Nanotube Arrays. ACS ES&T Engineering 2021, 1 (3) , 612-622.
  6. Guan Zhang, Juzhuan Ruan, Tingting Du. Recent Advances on Photocatalytic and Electrochemical Oxidation for Ammonia Treatment from Water/Wastewater. ACS ES&T Engineering 2021, 1 (3) , 310-325.
  7. Wenxiao Zheng, Liuyi Zhu, Sheng Liang, Jinshao Ye, Xin Yang, Zhenchao Lei, Zhang Yan, Yongdong Li, Chaohai Wei, Chunhua Feng. Discovering the Importance of ClO• in a Coupled Electrochemical System for the Simultaneous Removal of Carbon and Nitrogen from Secondary Coking Wastewater Effluent. Environmental Science & Technology 2020, 54 (14) , 9015-9024.
  8. Shasha Yang, Sujan Fernando, Thomas M. Holsen, Yang Yang. Inhibition of Perchlorate Formation during the Electrochemical Oxidation of Perfluoroalkyl Acid in Groundwater. Environmental Science & Technology Letters 2019, 6 (12) , 775-780.
  9. Yan Zhang, Jinhua Li, Jing Bai, Linsen Li, Shuai Chen, Tingsheng Zhou, Jiachen Wang, Ligang Xia, Qunjie Xu, Baoxue Zhou. Extremely Efficient Decomposition of Ammonia N to N2 Using ClO• from Reactions of HO• and HOCl Generated in Situ on a Novel Bifacial Photoelectroanode. Environmental Science & Technology 2019, 53 (12) , 6945-6953.
  10. Heonjin Ha, Kyoungsuk Jin, Sunghak Park, Kang-Gyu Lee, Kang Hee Cho, Hongmin Seo, Hyo-Yong Ahn, Yoon Ho Lee, Ki Tae Nam. Highly Selective Active Chlorine Generation Electrocatalyzed by Co3O4 Nanoparticles: Mechanistic Investigation through in Situ Electrokinetic and Spectroscopic Analyses. The Journal of Physical Chemistry Letters 2019, 10 (6) , 1226-1233.
  11. Changyong Zhang, Jinxing Ma, Jingke Song, Calvin He, T. David Waite. Continuous Ammonia Recovery from Wastewaters Using an Integrated Capacitive Flow Electrode Membrane Stripping System. Environmental Science & Technology 2018, 52 (24) , 14275-14285.
  12. Yang Yang, Li Cheng Kao, Yuanyue Liu, Ke Sun, Hongtao Yu, Jinghua Guo, Sofia Ya Hsuan Liou, Michael R. Hoffmann. Cobalt-Doped Black TiO2 Nanotube Array as a Stable Anode for Oxygen Evolution and Electrochemical Wastewater Treatment. ACS Catalysis 2018, 8 (5) , 4278-4287.
  13. Clément A. Cid, Justin T. Jasper, Michael R. Hoffmann. Phosphate Recovery from Human Waste via the Formation of Hydroxyapatite during Electrochemical Wastewater Treatment. ACS Sustainable Chemistry & Engineering 2018, 6 (3) , 3135-3142.
  14. Justin T. Jasper, Yang Yang, and Michael R. Hoffmann . Toxic Byproduct Formation during Electrochemical Treatment of Latrine Wastewater. Environmental Science & Technology 2017, 51 (12) , 7111-7119.
  15. Yang Yang and Michael R. Hoffmann . Synthesis and Stabilization of Blue-Black TiO2 Nanotube Arrays for Electrochemical Oxidant Generation and Wastewater Treatment. Environmental Science & Technology 2016, 50 (21) , 11888-11894.
  16. Justin T. Jasper, Oliver S. Shafaat, and Michael R. Hoffmann . Electrochemical Transformation of Trace Organic Contaminants in Latrine Wastewater. Environmental Science & Technology 2016, 50 (18) , 10198-10208.
  17. Lehui Ren, Mei Chen, Jinxing Ma, Yang Li, Zhiwei Wang. Pd–O2 interaction and singlet oxygen formation in a novel reactive electrochemical membrane for ultrafast sulfamethoxazole oxidation. Chemical Engineering Journal 2022, 428 , 131194.
  18. Tingting Du, Guan Zhang, Jing Zou. Coupling photocatalytic and electrocatalytic oxidation towards simultaneous removal of humic acid and ammonia−nitrogen in landscape water. Chemosphere 2022, 286 , 131717.
  19. Xingxin Liu, Chol Nam Song, Yuxin Zhang, Li Sha, Yiming Li, Shuting Zhang. Electrochemical pretreatment of coking wastewater by Ti/BTN/RuO2-IrO2-TiO2: Selectivity of chloridion oxidation and multi-response optimization. Separation and Purification Technology 2021, 276 , 119229.
  20. Haipeng Wang, Zhongkang Han, Yuanyi Zhou, Xuechen Liu, Di Zeng, Weimin Wang, Debalaya Sarker, Ling Zhang, Wenzhong Wang. Efficient photocatalytic chlorine production on bismuth oxychloride in chloride solution. Applied Catalysis B: Environmental 2021, 297 , 120436.
  21. Yan Zhang, Wenjing Tang, Jing Bai, Jinhua Li, Jiachen Wang, Tingsheng Zhou, Xiaohong Guan, Baoxue Zhou. Highly efficient removal of total nitrogen and dissolved organic compound in waste reverse osmosis concentrate mediated by chlorine radical on 3D Co3O4 nanowires anode. Journal of Hazardous Materials 2021, 326 , 127662.
  22. Meisam Soleimani, Jahan B. Ghasemi, Alireza Badiei. Black Titania; Novel researches in Synthesis and Applications. Inorganic Chemistry Communications 2021, 238 , 109092.
  23. Jintao Li, Xiaolong Zhou. The structural, electronic and optical properties of ZnTe/CdSe/GaSb heterotrilayer: first-principles study. Journal of Physics D: Applied Physics 2021, 54 (41) , 415104.
  24. Fan Zhang, Weilai Wang, Lei Xu, Chengzhi Zhou, Yanglong Sun, Junfeng Niu. Treatment of Ni-EDTA containing wastewater by electrochemical degradation using Ti3+ self-doped TiO2 nanotube arrays anode. Chemosphere 2021, 278 , 130465.
  25. Jia Zhang, Yaoyu Zhou, Bin Yao, Jian Yang, Dan Zhi. Current progress in electrochemical anodic-oxidation of pharmaceuticals: Mechanisms, influencing factors, and new technique. Journal of Hazardous Materials 2021, 418 , 126313.
  26. Yurou Zhou, Guan Zhang, Jing Zou. Photoelectrocatalytic generation of miscellaneous oxygen-based radicals towards cooperative degradation of multiple organic pollutants in water. Journal of Water Reuse and Desalination 2021,
  27. Jiaqi Sun, Lifen Liu, Fenglin Yang. Electro-enhanced chlorine-mediated ammonium nitrogen removal triggered by an optimized catalytic anode for sustainable saline wastewater treatment. Science of The Total Environment 2021, 776 , 146035.
  28. Yang Yu, Huachang Jin, Qian Li, Xuejiao Zhang, Yue Zhang, Xueming Chen. Pseudocapacitive Ti/RuO2-IrO2-RhOx electrodes with high bipolar stability for phenol degradation. Separation and Purification Technology 2021, 263 , 118395.
  29. Zexu Chi, Jingyun Zhao, Yi Zhang, Han Yu, Hongbing Yu. The fabrication of atomically thin-MoS2 based photoanodes for photoelectrochemical energy conversion and environment remediation: A review. Green Energy & Environment 2021, 43
  30. Qizheng Qin, Han Yang, Hongxiang Xu, Jiushuai Deng, Rong Zhao, Gen Huang, Penghui Wang, Jingzheng Wang. Experiment study on the separation of bituminous coal adsorption and the synergism of ultraviolet and electrochemistry in the pretreatment of coal chemical wastewater. Fuel 2021, 288 , 119712.
  31. Di Pang, Yue Liu, Haiou Song, Duozhe Chen, Weiqing Zhu, Rumeng Liu, Hu Yang, Aimin Li, Shupeng Zhang. Trace Ti3+- and N-codoped TiO2 nanotube array anode for significantly enhanced electrocatalytic degradation of tetracycline and metronidazole. Chemical Engineering Journal 2021, 405 , 126982.
  32. Han Yu, Zhuang Zhang, Linus Zhang, Heng Dong, Hongbing Yu. Improved Norfloxacin degradation by urea precipitation Ti/SnO2–Sb anode under photo-electro catalysis and kinetics investigation by BP-neural-network-physical modeling. Journal of Cleaner Production 2021, 280 , 124412.
  33. Jayeeta Saha, Indrajit Chakraborty, M.M. Ghangrekar. A novel tin-chloride-zirconium oxide-kaolin composite coated carbon felt anode for electro-oxidation of surfactant from municipal wastewater. Journal of Environmental Chemical Engineering 2020, 8 (6) , 104489.
  34. Yebin Lee, Yiseul Park. Ultrathin multilayer Sb-SnO2/IrTaOx/TiO2 nanotube arrays as anodes for the selective oxidation of chloride ions. Journal of Alloys and Compounds 2020, 840 , 155622.
  35. Yang Yang. Recent advances in the electrochemical oxidation water treatment: Spotlight on byproduct control. Frontiers of Environmental Science & Engineering 2020, 14 (5)
  36. Le Shi, Ruggero Rossi, Moon Son, Derek M. Hall, Michael A. Hickner, Christopher A. Gorski, Bruce E. Logan. Using reverse osmosis membranes to control ion transport during water electrolysis. Energy & Environmental Science 2020, 13 (9) , 3138-3148.
  37. Siva Kumar Varigala, Meghan Hegarty-Craver, Srinivas Krishnaswamy, Prakash Madhavan, Milan Basil, Praveen Rosario, Antony Raj, Viswa Barani, Clement A. Cid, Sonia Grego, Michael Luettgen. Field testing of an onsite sanitation system on apartment building blackwater using biological treatment and electrochemical disinfection. Environmental Science: Water Research & Technology 2020, 6 (5) , 1400-1411.
  38. Siwen Wang, Yanzhe Zhu, Yang Yang, Jing Li, Michael R. Hoffmann. Electrochemical cell lysis of gram-positive and gram-negative bacteria: DNA extraction from environmental water samples. Electrochimica Acta 2020, 338 , 135864.
  39. Yunting Wang, Yudong Xue, Chunhui Zhang. Generation and application of reactive chlorine species by electrochemical process combined with UV irradiation: Synergistic mechanism for enhanced degradation performance. Science of The Total Environment 2020, 712 , 136501.
  40. Jianan Gao, Bo Jiang, Congcong Ni, Yuanfeng Qi, Xuejun Bi. Enhanced reduction of nitrate by noble metal-free electrocatalysis on P doped three-dimensional Co3O4 cathode: Mechanism exploration from both experimental and DFT studies. Chemical Engineering Journal 2020, 382 , 123034.
  41. E. Richards, D. M. Murphy, M. Che. An EPR characterisation of stable and transient reactive oxygen species formed under radiative and non-radiative conditions. Research on Chemical Intermediates 2019, 45 (12) , 5763-5779.
  42. Jonghun Lim, Michael R. Hoffmann. Substrate oxidation enhances the electrochemical production of hydrogen peroxide. Chemical Engineering Journal 2019, 374 , 958-964.
  43. Xiaoyan Li, Jing Bai, Jinhua Li, Yan Zhang, Zhaoxi Shen, Li Qiao, Qunjie Xu, Baoxue Zhou. Efficient TN removal and simultaneous TOC conversion for highly toxic organic amines based on a photoelectrochemical-chlorine radicals process. Catalysis Today 2019, 335 , 452-459.
  44. Weijian Duan, Ge Li, Zhenchao Lei, Tonghe Zhu, Yuzhou Xue, Chaohai Wei, Chunhua Feng. Highly active and durable carbon electrocatalyst for nitrate reduction reaction. Water Research 2019, 161 , 126-135.
  45. Ling Gan, Yifan Wu, Haiou Song, Chang Lu, Shupeng Zhang, Aimin Li. Self-doped TiO2 nanotube arrays for electrochemical mineralization of phenols. Chemosphere 2019, 226 , 329-339.
  46. TsingHai Wang, Chih-Ang Lin, Su Xu, Chu-Fang Wang, Chiu-Wen Chen, Cheng-Di Dong, C.P. Huang. Toward concurrent organics removal and potential hydrogen production in wastewater treatment: Photoelectrochemical decolorization of methylene blue over hematite electrode in the presence of Mn(II). Applied Catalysis B: Environmental 2019, 244 , 140-149.
  47. Xiang Fan, Yurou Zhou, Guan Zhang, Tongzhou Liu, Wenyi Dong. In situ photoelectrochemical activation of sulfite by MoS2 photoanode for enhanced removal of ammonium nitrogen from wastewater. Applied Catalysis B: Environmental 2019, 244 , 396-406.
  48. Eleftheria Ntagia, Erika Fiset, Ligia da Silva Lima, Ilje Pikaar, Xu Zhang, Adriaan W. Jeremiasse, Antonin Prévoteau, Korneel Rabaey. Anode materials for sulfide oxidation in alkaline wastewater: An activity and stability performance comparison. Water Research 2019, 149 , 111-119.
  49. Cody E. Finke, Stefan T. Omelchenko, Justin T. Jasper, Michael F. Lichterman, Carlos G. Read, Nathan S. Lewis, Michael R. Hoffmann. Enhancing the activity of oxygen-evolution and chlorine-evolution electrocatalysts by atomic layer deposition of TiO 2. Energy & Environmental Science 2019, 12 (1) , 358-365.
  50. Li Deng, Yi Liu, Gan Zhao, Jiahao Chen, Shufan He, Yuchan Zhu, Bo Chai, Zhandong Ren. Preparation of electrolyzed oxidizing water by TiO2 doped IrO2-Ta2O5 electrode with high selectivity and stability for chlorine evolution. Journal of Electroanalytical Chemistry 2019, 832 , 459-466.
  51. Peng Li, Zhun Bao, Guanghui Wang, Pengfei Xu, Xuegang Wang, Zhipeng Liu, Yadan Guo, Jing Deng, Weimin Zhang. Ternary semiconductor metal oxide blends grafted [email protected] hybrid as dimensionally stable anode active layer for photoelectrochemical oxidation of organic compounds: Design strategies and photoelectric synergistic mechanism. Journal of Hazardous Materials 2019, 362 , 336-347.
  52. Yang Yang, Lin Lin, Leda Katebian Tse, Heng Dong, Shaokun Yu, Michael R. Hoffmann. Membrane-separated electrochemical latrine wastewater treatment. Environmental Science: Water Research & Technology 2019, 5 (1) , 51-59.
  53. Shouning Chai, Yujing Wang, Ya-nan Zhang, Hongying Zhao, Meichuan Liu, Guohua Zhao. Construction of a bifunctional electrode interface for efficient electrochemical mineralization of recalcitrant pollutants. Applied Catalysis B: Environmental 2018, 237 , 473-481.
  54. Yan Zhang, Jinhua Li, Jing Bai, Xiaoyan Li, Zhaoxi Shen, Ligang Xia, Shuai Chen, Qunjie Xu, Baoxue Zhou. Total organic carbon and total nitrogen removal and simultaneous electricity generation for nitrogen-containing wastewater based on the catalytic reactions of hydroxyl and chlorine radicals. Applied Catalysis B: Environmental 2018, 238 , 168-176.
  55. Liang Hong, Qiu Yang, Zhao Liying, Chen Yingyan, Wang Bing. Investigation of a novel pyrolusite particle electrode effects in the chlorine-containing wastewater. Water Science and Technology 2018, 78 (7) , 1427-1437.
  56. Changyong Zhang, Di He, Jinxing Ma, T. David Waite. Active chlorine mediated ammonia oxidation revisited: Reaction mechanism, kinetic modelling and implications. Water Research 2018, 145 , 220-230.
  57. Clément A. Cid, Yan Qu, Michael R. Hoffmann. Design and preliminary implementation of onsite electrochemical wastewater treatment and recycling toilets for the developing world. Environmental Science: Water Research & Technology 2018, 4 (10) , 1439-1450.
  58. Jianbing Wang, Dan Zhi, Hao Zhou, Xuwen He, Dayi Zhang. Evaluating tetracycline degradation pathway and intermediate toxicity during the electrochemical oxidation over a Ti/Ti4O7 anode. Water Research 2018, 137 , 324-334.
  59. Shaonan Wei, Liubin Shi, Zhandong Ren, Ailian Zhang, Ruoxi Ming, Bo Chai, Yuchan Zhu. Preparation of electrolyzed oxidizing water with a platinum electrode prepared by magnetron sputtering technique. RSC Advances 2017, 7 (72) , 45377-45384.