Self-assembly of Zn2SnO4 hollow microcubes and enhanced gas-sensing performances

Uniform Zn2SnO4 solid and hollow microcubes are synthesized via hydrothermal method followed by an annealing process in air. The morphology and structure were characterized by SEM, TEM and XRD. In addition, a possible formation mechanism of the hollow microcubes is discussed. The hollow Zn2SnO4 microcubes were found to exhibit higher and quicker response-recovery traits than these of solid nanocubes. Under the optimum operating temperature (260 °C), the response of hollow microcubes sensor to 200 ppm acetone is 141.7, which is 3 times larger than that of solid nanocubes (41.9). The significant decrease in response-recovery time is attributed not only to the surface accessibility allows by the hollow architectures, but also by numerous interweaving petal-like constructs of the nanoflowers.