Abstract
La element in La2/3Ca1/3MnO3 was partly replaced by Ho element, and highly Ho-doped (La1-xHox)2/3Ca1/3MnO3 (X = 0.2;0.3;0.4,0.5) nanocrystalline were synthesized by sol-gel method. Various techniques were carried out to investigate the influence of Ho element substitution on the structure, electrical and magnetic properties of the nanocrystalline. Results of x-ray diffraction (XRD) and scanning electron microscopy (SEM) confirms the perovskite structure of the Ho-doped (La1-xHox)2/3Ca1/3MnO3 nanocrystalline, and the grain size of samples monotonously decreased with the increase of Ho contents. M-T and dM/dT-T curves of samples showed that the phase transition region widened with the increase of Ho content. The connection became obvious between electromagnetic properties and changing of effective magnetic moment at x = 0.5. In addition, temperature dependence of resistivity curves performed by a conventional four-probe method was in agreement with the above result.
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