Sensitive detection of persulfate by a novel self-powered electrochemical sensor with carbon cloth electrodes modified with tin-doped cobalt tetroxide

• Published in: Environmental science and pollution research international 2024-10, Vol.31 (50), p.60451-60464
• Main Authors: Tang, Wanting, Liu, Weifeng, Li, Zhe, Liu, Ke, Jiang, Tao, Wang, Shanhui, Qu, Kai, Li, Jiayi, Zhang, Xingzhu, Zhu, Yimin
• Format: Article
• Language: English
• Subjects: Active sites; Aquatic Pollution; Atmospheric Protection/Air Quality Control/Air Pollution; Carbon; Carbon - chemistry; Carbon dioxide; Catalysis; Catalysts; Chemical reduction; Chemical sensors; Cloth; Cobalt; Cobalt - chemistry; Cobalt oxides; Decontamination; Earth and Environmental Science; Ecotoxicology; Electrochemical Techniques - methods; Electrochemistry; Electrodes; Electron transfer; Electrons; Environment; Environmental Chemistry; Environmental Health; Microorganisms; Oxides - chemistry; Potassium persulfate; Real time; Research Article; Sensors; Sulfates - chemistry; Tin; Tin - chemistry; Waste Water Technology; Water Management; Water Pollution Control
• ISSN: 1614-7499; 0944-1344; 1614-7499
• DOI: 10.1007/s11356-024-35214-5

The accurate and rapid detection of persulfate concentration is important for environmental decontamination and human health protection. In this work, a novel self-powered electrochemical sensor for the sensitive monitoring of persulfate was developed, which utilized cobalt tetroxide (Co 3 O 4 @CC) or tin-doped cobalt tetroxide (Sn x Co 3−x O 4 @CC) cathode as the sensing element and anode with electrogenic microorganisms as the power supplier. The Co 3 O 4 @CC and Sn x Co 3−x O 4 @CC electrodes were fabricated by in situ growing nanostructured Co 3 O 4 or Sn x Co 3−x O 4 catalysts on carbon cloth. Electrochemical tests revealed that these electrodes exhibited excellent catalytic reduction performance toward persulfate because of the synergistic catalysis by Co 3 O 4 and electrode electrons, well-exposed Co 2+ /Co 3+ catalytic sites, and high electron transfer efficiency. Tin doping could enhance the catalytic persulfate reduction by improving the conductivity and electron transfer of the Co 3 O 4 catalyst. The electrode prepared at a hydrothermal temperature of 90 °C and a tin dosage of 0.286 g·cm −2 achieved the highest persulfate reduction activity under pH 7. The sensing properties of the self-powered sensors toward persulfate were explored in detail. Results showed that under the optimal external load of 300 Ω, the proposed sensor could display a broad detection range of 0 to 1500 μmol L −1 K 2 S 2 O 8 with sensitivities of 1.13 and 0.12 μA μmol −1 L, a detection limit of 1.11 μmol L −1 (S/N = 3), and a fast response time within 30 s. The sensors also presented satisfactory reproducibility and selectivity during the detection of persulfate. The proposed sensor will provide a new approach for sensitive, on-site, and real-time monitoring of persulfate for a wide range of applications.