Assembly, formation mechanism, and enhanced gas-sensing properties of porous and hierarchical SnO₂hollow nanostructures

Hierarchical and hollow SnS₂nanostructures as precursors were fabricated via a surfactant-assisted assembly process using sodium dodecyl sulfate as soft templates. The as-prepared SnS₂nanostructures were further oxidized to form porous SnO₂conversion for investigating their gas-sensing properties in drug-precursor detection. On the basis of a series of time- and ratio-dependent reactions, a formation mechanism of the special nanostructures and factors influencing morphology and structure were determined. Gas-sensing measurements revealed that the porous and hierarchical SnO₂hollow nanostructures were sensitive to drug precursors, indicating promising applications in environmental monitoring and public safety investigation. In addition, we found that the assembled SnO₂nanomaterials possessed significantly enhanced gas-sensing properties compared with unassembled SnO₂with a solid interior.