Nanosheet-assembled hierarchical WO3 flower-like nanostructures: Hydrothermal synthesis and NH3-sensing properties.

Novel loosely and tightly arranged nanosheet-assembled flower-like WO 3 nanostructures were controllably synthesized under hydrothermal conditions. Through gas-sensing experiments towards NH 3 , it was found that the loosely-arranged WO 3 nanostructures exhibited a higher NH 3 response. This difference was due to the sparse cross-arrangement of the nanosheets on the surface of the sample and the larger specific surface area of the loosely-arranged structure. • Novel loosely and tightly arranged nanosheet-assembled flower-like WO 3 were synthesized. • The loosely-arranged WO 3 nanostructures exhibited the superior NH 3 sensing performance. • The factors affecting NH 3 -sensing properties are discussed in detail. Novel loosely and tightly arranged nanosheet-assembled flower-like WO 3 nanostructures were controllably synthesized via a facile hydrothermal approach. Additionally, NH 3 -sensing measurements were performed based on both samples. Remarkably, the loosely-arranged WO 3 nanostructures, which possess an abundance of semi-closed spaces and a larger specific surface area, exhibited improved NH 3 -sensing properties compared to that of the tightly-arranged WO 3 nanostructures. This discovery can provide guidance for improving the gas-sensing properties of nanosheet-assembled hierarchical MO x flower-like nanostructures. [ABSTRACT FROM AUTHOR]