The effect of Ni substitution on the magnetic properties of LaFeO3 nanofibers

LaFeO 3 has emerged as a highly promising candidate for gas sensors, photocatalysts, catalysts, and microwave absorber applications. LaNiO 3 is a highly prospective system for CO oxidation, photodegradation of tetracycline, ammonia decomposition, magnetic refrigeration, and oxygen evolution reaction. Doping LaFeO 3 with Ni is an efficient approach to tailor its crystal structure, electronic structure, as well as magnetic and electrical properties. A simple electrospinning and annealing way were used to fabricate LaFe 1−x Ni x O 3 nanofibers, such as LaFe 0.9 Ni 0.1 O 3 , LaFe 0.7 Ni 0.3 O 3 , LaFe 0.5 Ni 0.5 O 3 , LaFe 0.3 Ni 0.7 O 3 , and LaFe 0.1 Ni 0.9 O 3 . The structural transition from orthorhombic phase to rhombohedral phase were suggested by Rietveld refined XRD patterns. A Quantum Design SQUID vibrating sample magnetometer was employed to characterize the magnetic characteristics of these fabricated nanofibers. Magnetic properties of LaFe 0.9 Ni 0.1 O 3 and LaFe 0.7 Ni 0.3 O 3 were dominated by Fe 3+ –O–Fe 3+ antiferromagnetism. LaFe 0.5 Ni 0.5 O 3 exhibited intense competition between Fe 3+ –O–Fe 3+ , Ni 3+ –O–Fe 3+ , and Ni 3+ –O–Ni 3+ interactions. The magnetic behaviors of LaFe 0.3 Ni 0.7 O 3 and LaFe 0.1 Ni 0.9 O 3 were dominated by Ni 3+ –O–Ni 3+ exchange, showing paramagnetic state. The findings of this research can provide insights into the structure–property relationships in LaFe 1−x Ni x O 3 nanofibers and offer a materials design perspective for manipulating magnetic interactions.