Porous SnO₂ triple-shelled hollow nanoboxes for high sensitive toluene detection

A unique triple-shelled architecture with nonspherical shape has been successfully synthesized via a controllable multistep approach in case of polycrystalline SnO2 nanoboxes. The morphological characterizations demonstrate that SnO2 triple-shelled hollow boxes (THBs) are hierarchically constructed by numerous SnO2 primary nanoparticles. The formation mechanism of these SnO2 THBs is discussed based on a localized inside-out Ostwald ripening process. When SnO2 THBs are used as sensing material for toluene detection, the improved sensing performance can be attributed to the rational microstructures for fast transfer of gas molecules. (C) 2020 Elsevier B.V. All rights reserved.