Synthesis of α-Fe2O3 hollow spheres with rapid response and excellent selectivity towards acetone

Abstract Hollow spherical α-Fe2O3 nanopowders were prepared by using a combination of one-step hydrothermal method and annealing treatment. And the hydrothermal reaction time was systemically adjusted from 12 to 36 h. The crystalline structure, chemical state, elemental composition, and morphology of the samples were analyzed by such techniques as XRD, XPS, SEM, and TEM. Compared with other α-Fe2O3 nanomaterials, the samples synthesized within 24 h exhibit superior sensitivity, excellent selectivity, a rapid response/recovery speed, and good long-time stability for acetone. It has the highest response (46.6 to100 ppm acetone) and a low detection limit (1.51 to 1 ppm) for testing acetone under the optimal operating temperature (220.4 °C). Meanwhile, the response and recovery time are 1 and 12 s, respectively. The high absorption ability for acetone and hollow hierarchical structure may contribute to its excellent sensing performance.