Facile synthesis of single-crystalline hollow α-Fe2O3 nanospheres with gas sensing properties

High-quality single-crystalline hollow α-Fe2O3 nanospheres were prepared, using the ZnS–CHA (CHA = cyclohexylamine) nanohybrid as an additive through a solvothermal reaction, which avoids tedious steps and a high temperature calcination process. The formation process of these hollow nanospheres can be divided into two stages: (i) formation of solid Fe2O3 nanospheres and (ii) preferential inside-out dissolution of the solid nanoparticles to form hollow nanospheres. Due to the unique single-crystalline hollow structure, the as-obtained α-Fe2O3 nanomaterial exhibits enhanced gas sensing properties.