Abstract We report the structural, magnetic, magnetocaloric properties, and the critical behavior of the NiCeFeO4 spinel ferrite synthesized via the sol–gel method. The XRD analysis has revealed that NiCeFeO4 belongs to the Fd-3m space group of the cubic spinel structure. Furthermore, magnetic properties demonstrate that the prepared sample undergoes a second-order ferromagnetic-paramagnetic (FM-PM) phase transitions at TC = 640 K. Moreover, it was found that the maximum magnetic entropy change ( − Δ S M max ) at an applied magnetic field of 5 T is about 0.43 J kg−1K−1, corresponding to relative cooling powers (RCP) of 70.4 J kg−1. Finally, employing various experimental and theoretical techniques, the critical exponents deduced (β, γ and δ) in this study were observed to follow the Heisenberg theory in three dimensions, signifying short-range ferromagnetic interactions.

中文翻译：

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NiCeFeO4尖晶石铁氧体的结构、磁性、磁热效应及临界行为研究

摘要 我们报告了通过溶胶-凝胶法合成的 NiCeFeO4 尖晶石铁氧体的结构、磁性、磁热特性和临界行为。XRD分析表明NiCeFeO4属于立方尖晶石结构的Fd-3m空间群。此外，磁性表明制备的样品在 TC = 640 K 时经历了二阶铁磁 - 顺磁 (FM-PM) 相变。此外，发现在施加的最大磁熵变 (- Δ SM max ) 5 T 的磁场约为 0.43 J kg-1K-1，对应于 70.4 J kg-1 的相对冷却功率 (RCP)。最后，采用各种实验和理论技术，观察到本研究中推导出的临界指数（β、γ和δ）在三个维度上遵循海森堡理论，