Electrocatalytic Treatment of Pharmaceutical Wastewater by Transition Metals Encapsulated by B, N-Doped CNTs
The electrochemical advanced oxidation process is a promising technology for tackling wastewater pollution, but it suffers from poor pH adaptability and slow catalytic kinetics in a neutral and alkaline environment in a homogeneous system, as well as fast release of metal ions in a heterogeneous sys...
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MDPI AG
2023-11-01
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| Series: | Catalysts |
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| Online Access: | https://www.mdpi.com/2073-4344/13/12/1459 |
| _version_ | 1797381645586661376 |
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| author | Ou Sha Xifeng Lu Pei Su |
| author_facet | Ou Sha Xifeng Lu Pei Su |
| author_sort | Ou Sha |
| collection | DOAJ |
| description | The electrochemical advanced oxidation process is a promising technology for tackling wastewater pollution, but it suffers from poor pH adaptability and slow catalytic kinetics in a neutral and alkaline environment in a homogeneous system, as well as fast release of metal ions in a heterogeneous system. Herein, a boron- and nitrogen-codoped carbon nanotube-encapsulated transition metal (M@BN-C, M–Co, Cu) cathode with a similar structure was synthesized to explore activity trends and mechanisms. Characteristics of Co@BN-C and Cu@BN-C cathodes were examined and compared with the previously synthesized Fe@BN-C bifunctional cathode. The activity of sulfamethazine (SMT) degradation by the Co@BN-C cathode was higher than both Fe@BN-C and Cu@BN-C at pH = 3 and pH = 7, respectively. However, the activity of Co@BN-C was also higher than that of Cu@BN-C and lower than that of Fe@BN-C at pH = 9. It was observed that <sup>•</sup>OH and <sup>1</sup>O<sub>2</sub> were the main reactive oxygen species (ROS) using Co@BN-C and Cu@BN-C cathodes. The Co@BN-C generated the highest <sup>•</sup>OH for efficient SMT degradation through abundant H<sub>2</sub>O<sub>2</sub> generation, exhibiting the highest catalytic activity compared with the Cu@BN-C cathode. Overall, SMT degradation on the Co@BN-C cathode demonstrated better catalytic performance in real wastewater. This study provided insights into the fundamental catalytic trends and mechanisms of ROS production via the M@BN-C cathode, thus contributing to the development of the M@BN-C cathode for catalytic organic pollutant degradation. |
| first_indexed | 2024-03-08T20:54:24Z |
| format | Article |
| id | doaj.art-15a2df20b63f426b93b7959fd8d87834 |
| institution | Directory Open Access Journal |
| issn | 2073-4344 |
| language | English |
| last_indexed | 2024-03-08T20:54:24Z |
| publishDate | 2023-11-01 |
| publisher | MDPI AG |
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| series | Catalysts |
| spelling | doaj.art-15a2df20b63f426b93b7959fd8d878342023-12-22T13:59:20ZengMDPI AGCatalysts2073-43442023-11-011312145910.3390/catal13121459Electrocatalytic Treatment of Pharmaceutical Wastewater by Transition Metals Encapsulated by B, N-Doped CNTsOu Sha0Xifeng Lu1Pei Su2Hebei Key Laboratory of Applied Chemistry, College of Environmental and Chemical Engineering, Yanshan University, Qinhuangdao 066004, ChinaHebei Key Laboratory of Applied Chemistry, College of Environmental and Chemical Engineering, Yanshan University, Qinhuangdao 066004, ChinaHebei Key Laboratory of Applied Chemistry, College of Environmental and Chemical Engineering, Yanshan University, Qinhuangdao 066004, ChinaThe electrochemical advanced oxidation process is a promising technology for tackling wastewater pollution, but it suffers from poor pH adaptability and slow catalytic kinetics in a neutral and alkaline environment in a homogeneous system, as well as fast release of metal ions in a heterogeneous system. Herein, a boron- and nitrogen-codoped carbon nanotube-encapsulated transition metal (M@BN-C, M–Co, Cu) cathode with a similar structure was synthesized to explore activity trends and mechanisms. Characteristics of Co@BN-C and Cu@BN-C cathodes were examined and compared with the previously synthesized Fe@BN-C bifunctional cathode. The activity of sulfamethazine (SMT) degradation by the Co@BN-C cathode was higher than both Fe@BN-C and Cu@BN-C at pH = 3 and pH = 7, respectively. However, the activity of Co@BN-C was also higher than that of Cu@BN-C and lower than that of Fe@BN-C at pH = 9. It was observed that <sup>•</sup>OH and <sup>1</sup>O<sub>2</sub> were the main reactive oxygen species (ROS) using Co@BN-C and Cu@BN-C cathodes. The Co@BN-C generated the highest <sup>•</sup>OH for efficient SMT degradation through abundant H<sub>2</sub>O<sub>2</sub> generation, exhibiting the highest catalytic activity compared with the Cu@BN-C cathode. Overall, SMT degradation on the Co@BN-C cathode demonstrated better catalytic performance in real wastewater. This study provided insights into the fundamental catalytic trends and mechanisms of ROS production via the M@BN-C cathode, thus contributing to the development of the M@BN-C cathode for catalytic organic pollutant degradation.https://www.mdpi.com/2073-4344/13/12/1459electrocatalysiswater treatmentbifunctional cathodereactive oxygen speciesmechanism |
| spellingShingle | Ou Sha Xifeng Lu Pei Su Electrocatalytic Treatment of Pharmaceutical Wastewater by Transition Metals Encapsulated by B, N-Doped CNTs Catalysts electrocatalysis water treatment bifunctional cathode reactive oxygen species mechanism |
| title | Electrocatalytic Treatment of Pharmaceutical Wastewater by Transition Metals Encapsulated by B, N-Doped CNTs |
| title_full | Electrocatalytic Treatment of Pharmaceutical Wastewater by Transition Metals Encapsulated by B, N-Doped CNTs |
| title_fullStr | Electrocatalytic Treatment of Pharmaceutical Wastewater by Transition Metals Encapsulated by B, N-Doped CNTs |
| title_full_unstemmed | Electrocatalytic Treatment of Pharmaceutical Wastewater by Transition Metals Encapsulated by B, N-Doped CNTs |
| title_short | Electrocatalytic Treatment of Pharmaceutical Wastewater by Transition Metals Encapsulated by B, N-Doped CNTs |
| title_sort | electrocatalytic treatment of pharmaceutical wastewater by transition metals encapsulated by b n doped cnts |
| topic | electrocatalysis water treatment bifunctional cathode reactive oxygen species mechanism |
| url | https://www.mdpi.com/2073-4344/13/12/1459 |
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