Low-temperature hydrothermal synthesis of BiFeO ₃ microcrystals and their visible-light photocatalytic activity

Pure BiFeO ₃ (BFO) microcrystals were synthesized at the temperature as low as 120 °C via a urea-assisted hydrothermal process. The crystal structure, morphology and photocatalytic property of BFO microcrystals were investigated. The analysis reveals that the hydrolysis of urea in the hydrothermal process plays a key role in the synthesis of pure phase BFO microcrystals. FE-SEM and TEM results show that these BFO microcrystals present a nearly spherical microstructure, and specially exhibit superstructures consisting of large amounts of small particles with the size of 100-150 nm by further observation. Moreover, these BFO microcrystals exhibit efficient photocatalytic activity under visible-light irradiation, suggesting their promising applications as photocatalysts and related fields.