Hollow α-Fe2O3 quasi-cubic structures: Hydrothermal synthesis and gas sensing properties

• Hollow α-Fe2O3 cubes with hierarchical structure piled up by nano-sized particles were synthesized through a simple one-step hydrothermal method.
• The synthesis was performed in a water–isopropanol mixed solvent using ferrous chloride as the precursor without any templates.
• The results of sensing test found that the gas sensor based on as-prepared hollow cubes exhibited high response, good selectivity, fast response and recovery time to acetone at the operating temperature of 250 °C.

Hierarchical α-Fe2O3 quasi-cubic structures were synthesized through a simple one-step hydrothermal method. The synthesis was performed in a water–isopropanol mixed solvent using ferrous chloride as the precursor free of any templates. The images of field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM) indicated that the as-prepared α-Fe2O3 quasi-cubes had hollow interior. Moreover, these cubes showed a hierarchical structure, which were composed of densely packed nanoparticles. Subsequently, gas sensors based on the as-prepared hollow cubes were fabricated and their gas sensing performances were investigated. It was found that the gas sensor exhibited high response, good selectivity, fast response and recovery time to acetone at the operating temperature of 250 °C.