Magnetostructural transition and magnetocaloric effect in MnNiSi-Fe2Ge system

Magnetostructural transition from ferromagnetic orthorhombic phase to paramagnetic hexagonal phase can be obtained by chemically alloying appropriate amount of Fe2Ge into MnNiSi. The magnetostructural transition temperature is tunable in a wide temperature range of about 280 K. Saturation moment of the ferromagnetic orthorhombic phase increases from 2.62 μB/f.u. to 3.17 μB/f.u. with Fe2Ge-doping. The magnetostructural transition is accompanied by a large change of magnetization over 80 Am2/kg under magnetic field of 5 T. Relatively large magnetic entropy changes and working temperature ranges were observed in the vicinity of room temperature. Our findings suggest that MnNiSi-Fe2Ge material system is a promising platform for tunable magnetostructural transition and the associated magnetocaloric effect.