Simultaneous detection of 4-chlorophenol and 4-nitrophenol using a Ti3C2Tx MXene based electrochemical sensor

• Published in: Analyst (London) 2021-12, Vol.146 (24), p.7593-7600
• Main Authors: Ling, Lei, Li, Caoling, Huang, Wensheng, Wu, Kangbing
• Format: Article
• Language: English
• Subjects: Chemical sensors; Chlorophenol; Electron transfer; High performance liquid chromatography; Hydrothermal reactions; MXenes; Nitrophenol; Oxidation; Oxidation resistance; Toxicity; Wastewater
• ISSN: 0003-2654; 1364-5528
• DOI: 10.1039/d1an01799c

Developing a sensitive and rapid detection method for 4-chlorophenol (4-CP) and 4-nitrophenol (4-NP) is very important due to their high toxicity. In this work, bulk Ti3AlC2 powder was etched to Ti3C2Tx for the first time through a hydrothermal reaction in NaF/HCl solution. After ultrasonication in N-methylpyrrolidone (NMP), Ti3C2Tx powder was successfully exfoliated into multilayered Ti3C2Tx nanosheets (i.e. Ti3C2Tx MXene). The prepared Ti3C2Tx MXene not only has a large electrochemical surface area for the oxidation of 4-CP and 4-NP, but also lowers their electron transfer resistance. As a result, the oxidation signals of 4-CP and 4-NP are significantly improved on the surface of the Ti3C2Tx MXene. Based on the remarkable signal amplification of the Ti3C2Tx MXene, a sensitive and rapid method was developed for the simultaneous detection of 4-CP and 4-NP. The linear range is from 0.1 to 20.0 μM for 4-CP, and from 0.5 to 25.0 μM for 4-NP, with detection limits of 0.062 μM (4-CP) and 0.11 μM (4-NP). This method was used in wastewater samples, and the accuracy was confirmed to be good by high-performance liquid chromatography.