Abstract
The manner how nano building blocks assemble into hierarchical architectures exerts a tremendous influence on gas-sensing performance of the metal oxides. Here, we focus on tuning the 2D SnO2 nanosheets into 3D hierarchical nanoflowers by manipulating the presence of NaOH, and investigate their gas-sensing functionalities. We find that the blooming SnO2 nanoflowers assembled by ultrathin nanosheets (∼50 nm) are shrunk into semi-blooming state, and that the semi-blooming nanoflowers based sensor shows enhanced gas-sensing performance towards the ethanol, which is attributed mainly to the confined effect due to numerous nano or micro reaction rooms by keeping oxygen and ethanol molecules to complete gas-sensing reactions. While the semi-blooming nanoflowers turn into ordered mesoporous via thermally removing the periodically arranged polyvinyl pyrrolidone micelles, their gas-sensing performance is found to be improved dramatically, indicating that sufficient amount of gas diffusion is crucial to gas-sensing properties rather than the fast gas diffusion speed. As a final verification, we fabricate the sensors using the mesoporous semi-blooming SnO2 nanoflowers and successfully monitor the existence of beer by a simple integrated device, making it a promising candidate in detecting drunk driving.
Original language | English |
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Pages (from-to) | 120-128 |
Number of pages | 9 |
Journal | Sensors and Actuators, B: Chemical |
Volume | 231 |
DOIs | |
Publication status | Published - 2016 Aug 1 |
Keywords
- Gas diffusion
- Metal oxide
- Nanostructure
- Oxygen vacancy
- Sensor
ASJC Scopus subject areas
- Electrical and Electronic Engineering
- Condensed Matter Physics
- Electronic, Optical and Magnetic Materials
- Metals and Alloys
- Surfaces, Coatings and Films
- Materials Chemistry
- Instrumentation