Tuning structure and magnetic properties of table-like magnetocaloric effect in Er6MnSb2 by zirconium substitution

Abstract

In this study, zirconium (Zr) successfully substituted for erbium (Er) in Er6–xZrxMnSb2 (x = 0, 0.5, 1, 1.5) of the Fe2P type, with comprehensive characterizations on crystal structure, electronic structure and magnetic properties. According to synchrotron powder X-ray diffraction data analysis and density functional theory calculation, Zr does not randomly but preferentially occupy during the doping process and results in weaker magnetic exchange interactions and depressed ordering temperatures. The electronic structure data show that the doping of Zr can weaken interaction between Er and Mn atoms. Owing to multiple transitions, the Er6–xZrxMnSb2 (x = 0, 0.5, 1, 1.5) exhibit table-like magnetocaloric effect. Er6MnSb2 displays wide δTFWHM (full width at half maximum of the magnetic entropy change curve) of 116 K and high relative cooling power of 388.62 J/kg for 3 T. The maximum magnetic entropy change of Er6–xZrxMnSb2 is increased from 3.81 to 7.69 J/(kg·K) with the Zr content up from x = 0 to x = 1.5.