Low-temperature synthesis, structural and magnetic properties of self-dopant LaMnO3+δ nanoparticles from a metal-organic polymeric precursor

Self-dopant LaMnO3+δ nanoparticles have been successfully synthesized by metal citrate complex method based on Pechini-type reaction route, at low temperature (773 K). Powder X-ray diffraction and transmission electron microscope revealed pure and nanostructured phase of LaMnO3+δ (δ = 0.125) with an average grain size of ∼72 nm (773 K) and ∼80 nm (1173 K). DC-magnetization measurements under an applied magnetic field of H = ±60 kOe showed an increase in the magnetization with the increase of calcination temperature. Ferromagnetic nature shown by non-stoichiometric LaMnO3+δ was verified by well-defined hysteresis loop with large remanent magnetization (Mr) and coercive field (Hc). Surface areas of LaMnO3+δ nanoparticles were found to be 157.4 and 153 m2 g−1 for the samples annealed at 773 K and 1173 K, respectively.