Controllable assembly of sandwich-structured SnO2/Fe2O3 multilayer nanosheets for high sensitive acetone detection

A new type of hierarchically nonspherical architecture with sandwich-structured multilayer nanosheets has been successfully prepared via a controllable multistep approach in case of SnO2/Fe2O3 heterostructures. The morphological characterization reveals that unique sandwich-structured SnO2/Fe2O3 multilayer nanosheets (MNSs) are constructed via the self-assembly of densely well-aligned Fe2O3 nanorod layers to cover and fill the interlayers of hexagonal SnO2 hollow multilayer nanosheets (HMNs). When used as the sensing materials for acetone detection, the sandwich hetero-nanostructures demonstrate evidently improved sensing performance compared to pure SnO2. The significantly improved sensing performance can be attributed not only to the rational microstructures for fast transfer of gas molecules, but also to the additional effects of loaded Fe2O3 ultrathin nanorods.