N-doped three-dimensional needle-like CoS2 bridge connection Co3O4 core–shell structure as high-efficiency room temperature NO2 gas sensor

• Published in: Journal of hazardous materials 2022-02, Vol.423, p.127120-127120, Article 127120
• Main Authors: Bai, Xue, Liu, Zhuo, Lv, He, Chen, Junkun, Khan, Mawaz, Wang, Jue, Sun, Baihe, Zhang, Yang, Kan, Kan, Shi, Keying
• Format: Article
• Language: English
• Subjects: Bridge connection core–shell structure; High sensitivity; N-doped; P-p heterojunction; Room-temperature NO2 sensors
• ISSN: 0304-3894; 1873-3336
• DOI: 10.1016/j.jhazmat.2021.127120

The N-doped three-dimensional (3D) needle bridge connection core-shell structure N-CoS2@Co3O4 synthesized in this work was prepared by simple hydrothermal and high-temperature vulcanization methods. The optimized N-CoS2@Co3O4-2 composite response to NO2 is 62.3–100 ppm, a response time of 1.3 s, the recovery time of 17.98 s, the detection limit of 5 ppb and stability of as long as 10 weeks at room temperature (RT). Its excellent NO2 sensing performance is attributed to the unique porous and bridge connection core-shell structure of the N-CoS2@Co3O4-2 with high specific surface area, interconnected internal channels, abundant exposed S edge active sites, and high catalytic performance promoted by N-doping. This simple manufacturing method of high-performance sensing materials paves the way for the design of N-doped bridge connection core–shell structures. [Display omitted] •N-doped three-dimensional needle bridge connection core-shell structure N-CoS2@Co3O4 were synthesized by a simple strategy.•Unique porous and bridge connection core-shell structure provides the pathway for electron transfer and target gas diffusion.•The co-doping of S and N leads to the change of the charge density, which further increases the active sites.•Fast response and recovery time (1.3 s, 17.98 s), low detection limit (5 ppb).•The sensor maintains a good stability in the whole 10 weeks.