Bi_0.9Nd_{0. 1}Fe_1–xCo_xO₃ (x = 0.025, 0.050, 0.075 and 0.1) solid solutions have been synthesized by doping of Co³⁺ at the Fe³⁺ site using solid-state reaction method. The prepared solid solutions have been investigated for their structural, magnetic, ferroelectric and magneto-dielectric properties and conduction mechanism. The XRD study reveals that all the solid solutions possess a rhombohedral symmetry. The vibrating sample magnetometer study reveals that all the samples possess magnetic orders and the remnant magnetization has been found to be increased from 0.2388 emu/g for x = 0.025 to 0.7112 emu/g for x = 0.1. The non-Debye type dielectric relaxation has been investigated for all the samples. The frequency dependent ac conductivity data follows Jonscher’s Power law. Variation of exponent n versus temperature follows the overlapping large polaron tunneling conduction model. The maximum value of remanent polarization (∼0.152 μC/cm²) was found for x = 0.1. All the samples exhibit positive magneto-dielectric response in the low-frequency region with the highest magneto-capacitance value of 13.54% at 500 Hz for sample x = 0.1.

Bi _0.9 Nd _{0. 1} Fe _{1– x} Co _x O ₃ ( x = 0.025, 0.050, 0.075 and 0.1) 固溶体通过固相反应法在Fe ³⁺位点掺杂Co ³⁺合成。研究了制备的固溶体的结构、磁性、铁电和磁介电特性以及传导机制。XRD 研究表明所有固溶体都具有菱面体对称性。振动样品磁强计研究表明，所有样品都具有磁序，并且发现剩余磁化强度从 0.2388 emu/g 增加到x= 0.025 至 0.7112 emu/g，x = 0.1。已对所有样品研究了非德拜型介电弛豫。频率相关的交流电导率数据遵循 Jonscher 的幂定律。指数n随温度的变化遵循重叠的大极化子隧穿传导模型。当x = 0.1 时，发现剩余极化的最大值 (∼0.152 μC/cm ² ) 。所有样品在低频区域均表现出正磁介电响应，样品x = 0.1在 500 Hz 时的最高磁电容值为 13.54% 。