Abstract

Nanocrystalline Gd-doped soft Mn–Zn spinel ferrites with a generic formula Mn_0.5Zn_0.5Fe_2−xGd_xO₄ (x = 0.00, 0.04, 0.08 and 0.12) were synthesized using standard chemical co-precipitation technique. The powder X-ray diffractograms confirmed the phase purity of all the prepared samples along with average crystallite sizes in the range of 3 ± 1 nm. All the prepared nanoferrites displayed superparamagnetic behavior at room temperature as ensured by the room temperature hysteresis curves. The Néel temperature of all the prepared nanoferrites were below 50 K as seen from the M(T) curves. The indirect optical band gaps for all the Gd-doped nanoferrites were found in the range of 1.86 ± 0.02 eV. The variation of AC conductivity with applied electric field frequencies revealed that the hopping of electrons is the charge conduction mechanism of the nanoferrites.

中文翻译：

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掺软锰锌纳米铁氧体：合成，微观结构，磁性和介电特性

摘要

 使用标准的化学共沉淀技术合成了通式为Mn _0.5 Zn _0.5 Fe _{2− x} Gd _x O ₄（x = 0.00、0.04、0.08和0.12）的纳米晶掺Gd的软锰锌尖晶石铁氧体。粉末X射线衍射图证实了所有制备样品的相纯度以及在3±1nm范围内的平均微晶尺寸。所有制备的纳米铁氧体在室温下均表现出超顺磁性能，这由室温磁滞曲线确保。从M（T上可以看出，所有制备的纳米铁氧体的Néel温度都低于50 K。）曲线。所有掺杂Gd的纳米铁氧体的间接光学带隙为1.86±0.02 eV。交流电导率随施加的电场频率的变化表明，电子的跳跃是纳米铁氧体的电荷传导机制。