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This work reports the simultaneous observation of converse magnetoelectric (CME) and direct magnetoelectric (DME) effects in LaYFe2O6. The structural, magnetic, and magnetoelectric properties of LaYFe2O6, prepared by the sol-gel auto-combustion method and sintered at various temperatures, have been studied. The x-ray powder diffraction study suggests the double perovskite structure with symmetries P21nm (∼90%) and Pbnm (∼10%). The alternate ordering of La and Y ions is confirmed by the neutron powder diffraction (ND) study, which also suggests the antiferromagnetic (AFM) ordering of spins. AFM behavior is also manifested by the magnetic field-dependent magnetization (M) measurement. A higher P21nm phase content is desirable in the context of magnetoelectricity. Magnetic transition (∼700 K) is asserted in the temperature-dependent M measurement. The isothermal magnetization study shows weak ferromagnetism probably due to gradually increasing spin canting with temperature until the transition temperature. The highest CME coefficient (∼2.26 mOe cm/V) as well as DME coefficient (∼0.45 mV/cm Oe) in this material are recorded. True magnetoelectricity for temperature as high as 400 K opens up a new avenue on the playground of magnetoelectric (ME)-based applications.

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La2NiMnO6 is prepared for two different sintering time durations: 4 hour (4H) and 24 hour (24H). The magnetization data suggest a double ferromagnetic (FM) transition for 24H, whereas a single FM transition for 4H sample. The 4H sample was found to possess several microscopic pores compared with the 24H sample, and thus, these pores are vacuum impregnated with polyvinylidene fluoride (PVDF). The PVDF in the impregnated sample is found to crystallize in beta phase. The first and second order magnetoelectric coefficients are extracted from the measured data and plotted as a function of temperature. The room temperature region is found to be dominated by the magnetoconductivity/magnetoloss and thus resulting low ME voltage. With lowering of temperature, the situation improves, and for T < 200 K, the loss component becomes negligible so that the true magnetoelectricity is observed. A comparative study on all the three samples (4H, 24H, and 4H + PVDF) shows a significant enhancement in the magnetoelectricity in the 4H + PVDF sample. The highlight of this report is the unique way to arrest the porosity by PVDF impregnation into the pores of La2NiMnO6 so that leakage is minimized.