Bismuth substituted nickel ferrite (NiFe_2−xBi_xO₄ at x = 0.0–1.0) nanoparticles are synthesised by co-precipitation method. The crystal structure, grain size, morphology and magnetic properties are analysed by using XRD, FTIR, SEM, and VSM. XRD confirm the crystalline nature with single-phase cubic spinel structure. The average crystallite size calculated using Debye Scherrer and modified Scherrer formula is in the range of 20–65 nm. SEM image manifests that the particles are agglomerated and with non-uniformity shape. The presence of elemental composition such as Ni, Fe, Bi and O has been confirmed by EDX. In FTIR spectra, tetrahedral (A) and octahedral (B) sites are found in the range of 525–620 cm⁻¹ and 460–465 cm⁻¹, respectively. Their magnetic properties are scrutinized using VSM. At x = 0, the prepared nanoparticles are very useful for magnetic targeting carriers. The coercivity, saturation magnetization, remanence, squareness ratio, Bohr magneton and Curie temperature values decrease as the bismuth content increases. M–T curve reveals the superparamagnetic behaviour at room temperature.

铋取代的镍铁氧体（NiFe _{2− x} Bi _x O ₄ at x  = 0.0–1.0）纳米颗粒通过共沉淀法合成。使用XRD、FTIR、SEM和VSM分析晶体结构、晶粒尺寸、形貌和磁性能。XRD 证实具有单相立方尖晶石结构的结晶性质。使用 Debye Scherrer 和修正的 Scherrer 公式计算的平均微晶尺寸在 20-65 nm 范围内。SEM图像表明颗粒团聚且形状不均匀。EDX 证实了元素组成如 Ni、Fe、Bi 和 O 的存在。在 FTIR 光谱中，四面体 (A) 和八面体 (B) 位点位于 525–620 cm ^-1范围内和 460–465 cm ^-1，分别。使用 VSM 仔细检查它们的磁性。在x  = 0 时，制备的纳米粒子对于磁性靶向载体非常有用。矫顽力、饱和磁化强度、剩磁、矩形比、玻尔磁子和居里温度值随着铋含量的增加而降低。M-T 曲线揭示了室温下的超顺磁行为。