High sensitivity and low detection limit of acetone sensor based on Ru-doped Co3O4 flower-like hollow microspheres

• Published in: Sensors and actuators. B, Chemical Chemical, 2022-07, Vol.363, p.131839, Article 131839
• Main Authors: Jin, Rongrong, Jiang, Yueru, Zhao, Liupeng, Wang, Tianshuang, Liu, Xiaomin, Liu, Fangmeng, Yan, Xu, Sun, Peng, Lu, Geyu
• Format: Article
• Language: English
• Subjects: Acetone; Carrier density; Cobalt oxides; Flowers; Gas sensor; Gas sensors; High sensitivity; Hollow microflower; Microspheres; Oxygen; Ru-doped Co3O4; Ultra-low detection limit
• ISSN: 0925-4005; 1873-3077
• DOI: 10.1016/j.snb.2022.131839

In this paper, we successfully prepared Ru-doped Co3O4 flower-like hollow microspheres by a simple hydrothermal method. The microstructure characterization results indicated the formation of well-organized microflowers with a size of 0.5–1 µm, which were composed of nanosheets. The gas sensing performances of sensors by using the synthesized Ru-doped Co3O4 hollow microflowers as sensing material were investigated. The 1 at% Ru-doped Co3O4 sensor showed the best acetone sensing performance and had a response 18.8–10 ppm acetone, which was almost 5.4 times that of pure Co3O4. Significantly, the sensor had an ultra-low detection limit, with a response value of 1.5–50 ppb acetone at 137.5 °C (30%RH). We propose a plausible mechanism for sensing performance improvement. Namely, the substitution of Ru4+ regulated the carrier concentration and induced the change of Co3O4 defect oxygen and chemisorbed oxygen. •Ru-doped Co3O4 flower-like hollow microspheres were synthesized via a facile one-step hydrothermal method.•1 at% Ru-doped Co3O4 flower-like hollow microspheres exhibited better acetone gas sensing performance.•1 at% Ru-doped Co3O4 sensor had a response 18.8–10 ppm acetone at 137.5 ℃.•1 at% Ru-doped Co3O4 sensor had a low detection limit (50 ppb-1.5).