Microstructure and Magnetic Properties of LaMnO۳ Coatings via Electrophoretic Deposition

This study investigates the microstructural and magnetic properties of   LaMnO۳ coatings fabricated by electrophoretic deposition (EPD) on stainless steel substrates. LaMnO۳ powders were synthesized using a sol-gel citrate-nitrate auto-combustion method. The LaMnO۳ suspension was diluted to ۳۰ mg/۵۰ ml using a mixture of ethanol and deionized water. The concentration of deionized water was adjusted to ۱۰ mass% under an applied voltage of ۶۰ V for ۱۵ min. Surface morphology analysis revealed that the coating at ۶۰ V exhibited a uniform, higher-density structure with a surface roughness of ۳۰.۹۶ nm.  X-ray diffraction confirmed a rhombohedral structure with an R-۳c space group and revealed slight lattice expansions correlated with increasing annealing temperature. Fourier-transform infrared (FT-IR) spectroscopy revealed characteristic peaks at approximately ۵۸۰ cm⁻¹. This peak corresponds to an absorption band with a stretching mode associated with changes in the Mn–O–Mn bond length, which was an MnO۶ octahedron according to the vibration characteristics of ABO۳ perovskites. The magnetic properties, characterized using vibrating sample magnetometry (VSM), demonstrated that annealing at ۹۵۰ °C yielded the highest saturation magnetization (Ms = ۲.۳۷۷ emu/g), indicating enhanced ferromagnetic behavior due to increased Mn۳+/Mn۴+ interactions.

کلیدواژه ها:

LaMnO۳ ، sol-gel synthesis ، Electrophoretic deposition ، Surface roughness ، Magnetic properties