Observation of large magnetocaloric effect in equiatomic binary compound ErZn

Lingwei Li,Shengqiang Zhou,Yang Qi,Chi Xu,Ye Yuan

doi:10.1063/1.4972796

Lingwei Li, Shengqiang Zhou + Show 3 more

Open Access

https://doi.org/10.1063/1.4972796

Copy DOI

Abstract

The magnetism, magnetocaloric effect and universal behaviour in rare earth Zinc binary compound of ErZn have been studied. The ErZn compound undergoes a second order paramagnetic (PM) to ferromagnetic (FM) transition at Curie temperature of TC ∼ 20 K. The ErZn compound exhibits a large reversible magnetocaloric effect (MCE) around its own TC. The rescaled magnetic entropy change curves overlap with each other under various magnetic field changes, further confirming the ErZn with the second order phase transition. For the magnetic field change of 0-7 T, the maximum values of the magnetic entropy change (−ΔSMmax), relative cooling power (RCP) and refrigerant capacity (RC) for ErZn are 23.3 J/kg K, 581 J/kg and 437 J/kg, respectively.

Highlights

A giant reversible low field magnetocaloric effect (MCE) was observed in TmZn, the maximum value of magnetic entropy change is as high as 19.6 J/kg K for a low magnetic field change of 0-2 T, indicating that TmZn could be a promising candidate for low temperature magnetic refrigeration.[11]
Temperature dependence of magnetization (M, left scale) and the reciprocal susceptibility (1/χ = H/M, right scale) for ErZn under the high magnetic field of H = 1 T is presented in Fig. 1, and the inset illustrates the temperature dependence of the zero field cooled (ZFC) and field cooled (FC) magnetization (M) for ErZn under the low magnetic field of H = 0.1 T
For the magnetic field changes of 0-2, 0-5, and 0-7 T, the maximum values of the magnetic entropy change (−∆SMmax) are 9.8, 19.1, and 23.3 J/kg K, respectively, indicating the present ErZn compound belonging to a family of large MCE materials

Summary

INTRODUCTION

Magnetic refrigeration technology based on the magnetocaloric effect (MCE) has been widely investigated due to its higher energy efficiency and more environment friendly as compared to conventional gas compression and expansion refrigeration.[1,2,3] many magnetic alloys and oxides have been prepared and systematically studied with respect to magnetocaloric properties in recent years, and found that some of them could be excellent candidate materials for active magnetic refrigerant.[1,2,3,4,5,6,7] The equiatomic binary compounds of rare earth Zinc (REZn) crystallized in the cubic CsCl-type structure belonging to Pm3m space group have been investigated due to its simple crystal structure with interesting properties.[8,9,10,11] Some basic properties (magnetic, thermal, electrical, magnetocaloric and elastic properties) for selected REZn compounds have been reported experimentally in the literatures.[8,9,10,11] Very recently, a giant reversible low field MCE was observed in TmZn, the maximum value of magnetic entropy change is as high as 19.6 J/kg K for a low magnetic field change of 0-2 T, indicating that TmZn could be a promising candidate for low temperature magnetic refrigeration.[11] To continue of these series studies, we have further investigated the magnetic and magnetocaloric properties of ErZn in this work

EXPERIMENTAL DETAILS

RESULTS AND DISCUSSION

CONCLUSIONS