Ultrathin nanorod-assembled SnO2 hollow cubes for high sensitive n-butanol detection

A new type of nonspherical hollow nanocubes functionalized with well-aligned rodlike building blocks have been successfully prepared via a facile one-pot hydrothermal approach in case of SnO2. The structural and morphological characterization reveals that the dense rodlike SnO2 subunits are vertically distributed on all of the six equivalent facets of cubic structure. The rodlike primary building blocks with a uniform diameter of about 5 nm exhibit a single-crystalline rutile structure. A two-step sequential growth model is proposed based on observation from a time-dependent evolution process, revealing that the initially formed of well-defined ZnSn (OH)(6) solid cubes can serve as sacrifice self-template for the interior hollowing and vertical growth of SnO2 nanorods. Moreover, gas sensor based on SnO2 nanocages exhibits the enhanced sensing performances to n-butanol. The significant decrease in response-recovery time can be attributed not only to the interior cavities combined with permeable shells for fast transfer of gas molecules, but also to these high-activated rodlike subunits with ultrathin diameter.