Facile synthesis of hierarchical carpet-like WO_3 microflowers for high NO_2 gas sensing performance

摘要

Highlights•Hierarchical carpet-like WO3microflowers with triclinic thin bundle-like nanostructure were prepared.•The formation of hierarchical carpet-like structure is adjusted by oleic acid.•The WO3microflowers show excellent gas sensing performance for NO2with good sensitivity and reproducibility.AbstractThe hierarchical carpet-like WO3microflowers were synthesized via a facile one-step hydrothermal method by using oleic acid as a oriented growth reagent. The as-synthesized WO3microflowers show a triclinic crystal structure and are basically hierarchical assemblies of carpet-like nanosheets made up of the subunit of bundle-like nanowires. Based on the morphology evolution process, a possible crystal growth and nanostructure assembling mechanism were proposed. The prepared WO3microflower sensor exhibits a gas sensing response of about 228 when exposed to 10ppm of toxic NO2gas at 200°C.