N-doped clay-like Ti3C2Tx MXene/N-doped CNTs composites for ethylene glycol detection in ambient air and exhaled breath

• Published in: Electrochemistry communications 2024-07, Vol.164, p.107738, Article 107738
• Main Authors: Shi, Zhiwen, Qiao, Lijuan, Ma, Mei, Jia, Zhi, Liu, Bingxin, Gao, Li
• Format: Article
• Language: English
• Subjects: Ethylene glycol; Gas sensors; N-CNTs; N-Ti3C2Tx MXene; Room temperature
• ISSN: 1388-2481; 1873-1902
• DOI: 10.1016/j.elecom.2024.107738

•N-CNTs was successfully distributed between layers and surfaces of N-doped Ti3C2Tx MXene by electrostatic self-assembly to provide adsorption and reaction sites for ethylene glycol.•N-Ti3C2Tx MXene/N-CNTs has high sensitivity and selectivity to ethylene glycol in ambient air and exhaled breath.•The ethylene glycol sensor device has been prepared through custom-made circuit boards and sensing programs.•The adsorption and oxidation process of ethylene glycol on the N-Ti3C2Tx MXene/N-CNTs was explored by in situ infrared spectra testing to reveal that electrocatalysis of N-CNTs played an important role in the selective detection of ethylene glycol. Ethylene glycol is odorless and harmful to humans. Each year, a large number of fatal cases are caused by ethylene glycol poisoning. Therefore, rapid identification of ethylene glycol is crucial. In this study, clay-like Ti3C2Tx MXene exhibits a larger interlayer spacing compared to accordion-like Ti3C2Tx MXene, which enhances the gas diffusion channels. Nitrogen doping can increase the active sites of clay-like Ti3C2Tx MXene. The introduction of nitrogen-doped carbon nanotubes into N-Ti3C2Tx was carried out to enhance selectivity towards ethylene glycol, leading to the formation of N-Ti3C2Tx MXene/N-CNTs. The N-Ti3C2Tx MXene/N-CNTs exhibits significant selectivity towards the ethylene glycol at room temperature. Meanwhile, the detection limit was 0.3484 ppm, with a shortened response/recovery time of 10.57/6.29 s. Meanwhile, the ethylene glycol sensor device has been prepared through custom-made circuit boards and sensing programs. Moreover, the adsorption and oxidation process of ethylene glycol on N-Ti3C2Tx MXene/N-CNTs was explored through in-situ infrared spectroscopy testing. This study revealed that the oxygen vacancies on the surface of N-Ti3C2Tx MXene/N-CNTs play a crucial role in the oxidative catalytic detection of ethylene glycol. The strategy of N-Ti3C2Tx MXene/N-CNTs provides a new avenue for the detection of ethylene glycol.