Polycrystalline YFeO3 (YFO) and YFe1−(4/3)xTixO3(YFTO) ceramics were prepared using the powder synthesized from the sol‐gel route. X‐ray diffraction analyses of the polycrystalline ceramics revealed the crystallization of the phase in orthorhombic crystal structure associated with the space group Pnma. The magnetization versus magnetic field hysteresis loops were obtained at room temperature for YFO and YFTO ceramics. The magnetic property changes from weak ferromagnetic in YFO to ferromagnetic in YFTO ceramics. The dielectric constant recorded at room temperature for YFTO ceramics was six times higher than that of YFO, whereas the dielectric loss gets reduced to 0.06 from 0.3 for YFO at 1 kHz. Impedance spectroscopy study carried out on YFO and YFTO ceramics confirmed the existence of non‐Debye‐type relaxation. Observed single semicircle in Z′ vs −Z′′ plot established the incidence of intrinsic (bulk) effect and ruled out any grain boundary or electrode effects. The mechanism for the dielectric relaxation and electrical conduction process observed in YFO and YFTO ceramics was discussed by invoking electric modulus formalisms. Activation energy obtained by ac conductivity study suggested that the conduction process in YFO was linked up with the existence of the polaron and oxygen vacancies, whereas only oxygen vacancies contribute to the conduction process in YFTO ceramics.

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Polycrystalline BiFeO 3 and Bi 0.9 Gd 0.1 Fe 1−x Ti x O 3 (x = 0, 0.01, 0.05 and 0.1) samples were synthesized by solid-state reaction route. Structural, magnetic and ferroelectric properties of these samples were investigated. X-ray powder diffraction (XRD) results confirmed the presence of a significant amount of Bi 2 Fe 4 O 9 impurity phase in the undoped BiFeO 3 sample. Mössbauer spectroscopy studies corroborated the XRD studies to confirm the presence of impurity phase. We have observed that gadolinium (Gd 3+) and titanium (Ti 4+) doping, respectively, on Bi 3+ and Fe 3+ sites facilitated a significant reduction in the impurity phase formation in BiFeO 3. Interestingly, Gd 3+doping significantly reduced the impurity phase formation as compared to the undoped BiFeO 3 sample. This impurity phase formation was further overcome by doping higher (x ≥ 0.05) amounts of Ti in BiFeO 3. The crystallographic site occupancies of Gd and Ti were confirmed by Rietveld refinement of XRD data, Mössbauer spectroscopy and magnetization measurements. An enhancement in ferromagnetic properties along with moderate ferroelectric properties have been observed after co-doping. There was an increasing trend in remnant polarization (P r) with the increase in Ti concentration besides an improvement in the characteristic saturation magnetization. Our results demonstrate that Gd 3+ and Ti 4+ doping could be used to enhance multifunctional properties of BiFeO 3 ceramics to enable them as potential material for various devices.

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