Self-assembly of hierarchical ZnSnO3-SnO2 nanoflakes and their gas sensing properties
(State Key Laboratory of Superhard Materials; Key Laboratory of Automobile Materials, Ministry of Education;
College of Materials Science and Engineering, Jilin University, Changchun 130012, China)
College of Materials Science and Engineering, Jilin University, Changchun 130012, China)
Abstract: A new type of hierarchical ZnSnO3-SnO2 flower-shaped nanostructure composed of thin nanoflakes as secondary units is successfully prepared through a simple hydrothermal process. The polyhedral ZnSnO3 core acts as a sacrificed template for the growth of hierarchical SnO2 nanoflakes, and the average thickness of SnO2 nanoflakes is around 25 nm. The time-dependent morphology evolution of ZnSnO3-SnO2 samples was investigated, and a possible formation mechanism of these hierarchical structures is discussed. The gas sensor based on these novel ZnSnO3-SnO2 nanostructures exhibits high response and quick response- recovery traits to ethanol (C2H5OH). It is found that ZnSnO3-SnO2 nanoflakes have a response of 27.8 to 50×10-6 C2H5OH at the optimal operating temperature of 270 °C, and the response and recovery time are within 1.0 and 1.8 s, respectively.
Key words: complex nanostructure; hierarchical structure; hydrothermal synthesis; gas sensor