Novel Pd-doped-CuO/Ti3C2Tx integrated nanocomposite with improved performance for low-concentration hexanal detection

• Published in: Ceramics international 2024-11
• Main Authors: Chai, Xiaojie, Zhang, Kaibin, Wang, Miaoru, Sang, Shengbo, Hu, Xiaobing
• Format: Article
• Language: English
• Subjects: CuO; Gas sensor; Hexanal; MXenes; Nanocomposite; Pd-doped
• ISSN: 0272-8842
• DOI: 10.1016/j.ceramint.2024.11.167

Monitoring hexanal gas at parts per billion (ppb) levels is significantly challenging. Among sensing materials, MXenes with abundant active sites, controllable surface chemistry, and tunable conductivity have shown particular promise in gas sensing of hexanal gas, but pure MXenes still suffer from low sensitivity and baseline drift. Herein, p-type metal oxide Pd-doped-CuO adhering to surfaces and interlayers of the Ti3C2Tx was fabricated to yield sensing platforms. The formation of p-p heterojunctions enhanced the responses of Pd-doped-CuO/Ti3C2Tx gas sensor toward detection of hexanal at 150 °C by more than 3.2-fold when compared to pure Ti3C2Tx. The nanocomposite sensor also exhibited an ultra-low detection limit of 0.1 ppm, faster response-recovery time (19/40 s), and good stability (30 days) for trace hexanal detection. The improved gas-sensing mechanism based on the formation of p-p heterojunctions, sufficient reactive centers provided by CuO, and promoted catalytic ability of PdO.