Shape-controlled preparation of bismuth ferrite by hydrothermal method and their visible-light degradation properties

• Facile synthesis of BiFeO3 (BFO) with destined morphology and particle size.
• The influences of KOH concentration, reaction time and dispersant are clarified.
• BFO has tunable visible-light response and can efficiently degrade methyl orange.
• Photodegradation of MO under visible light is found to be shape-related.
• Reaction mechanism is proposed and the active species are convinced by EPR.

Bismuth ferrite (BiFeO3) has been prepared by hydrothermal method using Fe(NO3)3·9H2O and Bi(NO3)3·5H2O as the starting materials. The single-phase cube-like BiFeO3 materials with defined morphologies were successfully synthesized by controlling the experimental parameters. Effects of reaction time, KOH concentration and organic dispersant on the BiFeO3 particle morphology, size and property were systematically investigated. The prepared BiFeO3 particles present tunable absorption characters by controlling the particle size and morphology. The prepared samples can degrade methyl orange (MO) under visible light (>420 nm). Cubic BiFeO3 particles with a size of ca.1.4 um could be synthesized by using PVP as the dispersant, which shows the highest activity of MO photo-degradation. The photocatalytic mechanism is proposed and active components are further convinced by EPR analysis.

BiFeO3 with tunable particle morphologies and visible-light responses could be synthesized by controlling KOH concentration, reaction time and dispersant. The prepared samples can effectively degrade MO under visible light and the performance is driven by specific particle shape.Figure optionsDownload as PowerPoint slide