Nanosheets-assembled hollowed-out hierarchical Co3O4 microrods for fast response/recovery gas sensor

• Published in: Sensors and actuators. B, Chemical Chemical, 2017-10, Vol.249, p.66-75
• Main Authors: Tan, Wenhu, Tan, Jianfeng, Li, Long, Dun, Menghan, Huang, Xintang
• Format: Article
• Language: English
• Subjects: Co3O4; Fast response/recovery; Gas sensor; Hollowed-out hierarchical microrods; Thin nanosheets
• ISSN: 0925-4005; 1873-3077
• DOI: 10.1016/j.snb.2017.04.068

•The hollowed-out hierarchical Co3O4 microrods were synthesized via interfacial-reaction of CoC2O4·2H2O with NaOH.•The Co3O4 samples were assembled by interlaced thin nanosheets (with thickness of around 7nm).•Response/recovery time of the gas sensor to 100ppm methanol and ethanol are 0.8/7.2s and 0.8/10.8s, respectively.•The Co3O4 microrods could be a promising candidate as a sensing material for real-time monitoring gas sensor. Hollowed-out hierarchical Co3O4 microrods has been synthesized via the interfacial-reaction of CoC2O4·2H2O with NaOH. Field emission scanning electron microscopic and transmission electron microscopic results revealed that the Co3O4 samples were hollowed-out hierarchical microrod-like structure assembled by interlaced thin nanosheets (with thickness of around 7nm). The gas sensing properties of the porous microrods Co3O4 were evaluated. The response/recovery time of the gas sensor to 100ppm methanol and ethanol are 0.8/7.2s and 0.8/10.8s, respectively. Gas sensing measurement revealed that the hollowed-out hierarchical Co3O4 microrods exhibit high performance, especially fast response/recovery characteristics to methanol and ethanol. The enhancement of gas sensing properties is attributed to the thin thickness of nanosheets, large specific surface area, loose interior and through-pore structure. The good sensing performance suggests this hollowed-out hierarchical Co3O4 microrods could be a promising candidate as a sensing material for real-time monitoring gas sensor.