A Liquid-Precursor Synthesis of Single-Phase Magnetoelectric LaFeO₃ Nanocrystallites

LaFeO₃, a nontoxic and thermally stable compound, when prepared of small crystallites offers tailored magnetic and magnetoelectric properties at room temperature. In this article, we describe synthesis of a phase pure LaFeO₃ of nanocrystallites with a bonded carbon surface layer from a liquid precursor at moderate temperature in air. The results demonstrate that, upon sonication and microwave heating, the metal ions La³⁺ and Fe³⁺ in an inorganic-organic precursor cluster and grow into LaFeO₃ crystallites in a specific shape of nanoplates, typically 40–150 nm in width and 15–25 nm in thickness, at moderate temperature ∼700 °C in ambient air. The stable phase LaFeO3 stands in an orthorhombic crystal structure (Pnma space group), on sintering to obtain useful ferroelec- tric properties in a dense pellet. At room temperature, a sintered pellet (at 950 °C for 4 h) measures a wide ferroelectric hysteresis loop, showing a polarization of 2.05 μC/cm², remnant polarization of 0.78 μC/cm², and coercivity 7.65 kV/cm for an applied electric field up to 18 kV/cm (at 500 Hz). These values are compatible to those known in important granular multiferroics such as BiFeO³ and composites.