Facile synthesis and enhanced gas sensing properties of In2O3 nanoparticle-decorated ZnO hierarchical architectures

Abstract

In₂O₃ nanoparticle-decorated flowerlike ZnO hierarchical architectures are fabricated by a simple and facile two-step approach, including the room temperature synthesis of flowerlike ZnO and the subsequent decoration with In₂O₃ nanoparticles, and developed for HCHO gas detection. The SEM, TEM and HRTEM images indicate that the In₂O₃ nanoparticles have successfully grown and are closely attached to the surface of the ZnO. The special 3D hierarchical architectures, the appropriate decoration amount of In₂O₃ nanoparticles and the incorporation of interfaces between ZnO nanosheets and the In₂O₃ nanoparticles endow In₂O₃-decorated ZnO nanostructured sensors with enhanced HCHO gas sensing performances. A multistage reaction formation mechanism of flowerlike hierarchical nanostructures and a morphology-dependent sensing mechanism are proposed.