Low-temperature synthesis of high-purity BiFeO3 via carbonized metal citrate xerogel

• Published in: Journal of alloys and compounds Vol. 843; p. 155928
• Main Authors: Zaki, Mohamed I., Nohman, Ahmed K.H., Mekhemer, Gamal A.H., Mohamed, Hagar A.A.
• Format: Journal Article
• Language: English
• Published: Lausanne Elsevier B.V 30.11.2020; Elsevier BV
• Subjects: Bi/Fe-citrate xerogel; Bismuth ferrite; Differential thermal analysis; Fourier transforms; High-purity bismuth ferrite; Infrared analysis; Infrared spectrophotometers; Iron; Low temperature; Product characterization; Roasting; Sol-gel processes; Sol-gel processing; Spectrophotometry; Thermal decomposition; Ultraviolet reflection; Xerogels; Bi/Fe-citrate xerogel; Product characterization; High-purity bismuth ferrite; Sol-gel processing; Thermal decomposition
• ISSN: 0925-8388; 1873-4669
• DOI: 10.1016/j.jallcom.2020.155928

Bi/Fe-citrate xerogel, prepared by sol-gel processing, was first carbonized and, then, calcined at 300–700 °C for 1 h. The gel and its calcination products were characterized by thermal analyses (TG/DTA), X-ray powder diffractometry (XRD), Fourier-transform infrared spectrophotometry (FTIR), BET-specific surface area measurement (SBET), and Ultraviolet–Visible diffuse reflectance spectrometry (UV–Vis DRS). It was found that the carbonization step helps to subside the effects of a glowing thermal decomposition event, thus suppressing the formation of parasitic phases (such as Fe2O3 and Bi2Fe4O9). Rhombohedral-BiFeO3 yielded at 500 °C was found to assume qualifying properties for photo-assisted applications. [Display omitted] •Bi/Fe-citrate xerogel is obtained via sol-gel processing and drying at 80 °C.•Thermal decomposition (in air) of the gel encompasses a glowing event near 300 °C.•Impacts of the heat released are subsided via 400 °C pre-carbonization of the gel.•Consequently, 500 °C calcination of the carbonized gel yields pure BiFeO3.•The BiFeO3 assumes qualifying properties for photo-assisted applications.