Facile synthesis of bamboo raft-like Co3O4 with enhanced acetone gas sensing performances

Highlights: • Unique Co₃O₄ architectures are fabricated by a facile two-step route. • Nanoparticles-assembled Co₃O₄ architectures present bamboo raft-like structure. • The bamboo raft-like Co₃O₄ is of wider inter-particles contact width. • Co₃O₄ architectures based sensors show excellent acetone gas sensing performances. • Wider inter-particle contact width and planar structures improve sensing property. The designed synthesis of bamboo raft-like Co₃O₄ has been achieved by a facile one-step room temperature solution process followed by subsequent annealing. The morphology and structure characterizations from SEM, TEM and XRD indicate that numerous Co₃O₄ granular chains are orderly assembled in a planar connection way to construct bamboo raft-like architectures. To demonstrate the potential application, the as-prepared bamboo raft-like Co₃O₄ is employed and developed for acetone gas detection. In comparison with Co₃O₄ micro/nanospheres, bamboo raft-like Co₃O₄ not only exhibits almost three times higher sensitivity, but also shows faster response and recovery speed (shorten by 58 s and 17 s, respectively) towards 200 ppm acetone gas. Importantly, bamboo raft-like Co₃O₄ possesses advantages of lower operating temperature and better reversibility. Such impressive features are mainly attributed to the contact pattern of internal nanoparticles and planar bamboo raft-like architectures, which provide more exposed surface areas for gas adsorption and surface chemical reaction and larger contact width between nanoparticles for conduction, thus exhibiting a higher acetone gas sensing performance. The bamboo raft-like architecture provides a solid evidence to clarify the contribution of the assembly pattern of building blocks to gas sensing behaviors.