In₂O₃ Hollow Microspheres: Synthesis from Designed In(OH)₃ Precursors and Applications in Gas Sensors and Photocatalysis

Abstract

In this work, well-shaped In(OH)3 hollow microspheres have been successfully prepared via a novel surfactant-free vesicle−template−interface route in the “formamide−resorcinol−water” system, in which spontaneous vesicles were formed under hydrothermal conditions and NH3 from the hydrolysis of formamide acted as the OH- provider. Morphological and structural characterizations indicate that the shells of as-prepared In(OH)3 hollow microspheres were constructed by numerous nanocubes about 80 nm in size. As desired, In2O3 hollow microspheres were obtained from annealing the designed In(OH)3 precursors, and the as-obtained In2O3 hollow microspheres performed well as a gas-sensing material in response to both ethanol and formaldehyde gases and as a photocatalyst for photocatalytic degradation of rhodamine B. The facile preparation method and the improved properties derived from special microstructures are significant in the synthesis and future applications of functional nanomaterials.