Hydroxylation surfaces dominantly enhanced xylene sensing dynamics in CuCo2O4/CuO/Cu heterostructures

• Published in: Journal of alloys and compounds 2025-01, Vol.1010, p.177563, Article 177563
• Main Authors: Feng, Yanxu, Hu, Chenlu, Du, Mengying, Zhang, Lifang, Jiang, Rui, Wang, Shuangming, Cao, Jing
• Format: Article
• Language: English
• Subjects: Hydroxylated surface; Reduction treatment; Selectivity; Xylene
• ISSN: 0925-8388
• DOI: 10.1016/j.jallcom.2024.177563

The surface hydroxylation is a feasible strategy for optimizing the performance of functional materials, but is rarely applied in gas sensing field and the parallel gas sensing improvement mechanism has not been clearly revealed. Herein, sodium borohydride (NaBH4) induced reduction treatment is proposed to engineer the surfaces of CuCo2O4/CuO composite sensing materials. The surface metal hydroxyl groups (M-OH) or hydroxyl groups (-OH) of as-prepared CCO-0.3 materials (treating CuCo2O4/CuO by 0.3 mmol/L NaBH4 solution) specifically adsorb xylene gas via methyl groups through noncovalent interactions. Thus, hydroxylated surfaces promote xylene gas recognition and signal conversion, and bring significantly enhanced xylene response and sensing selectivity. This reduction strategy holds great promise for improving the performances of various gas sensing materials. [Display omitted] •The NaBH4 treatment is employed to optimize gas sensing dynamics.•Hydroxylated surfaces promote xylene gas adsorption and recognition.•CuCo2O4/CuO/Cu shows prominently enhanced xylene gas selectivity.