Measurement protocols dependent giant magnetocaloric effect in MnNiSi-based system

MnNiSi-based compounds exhibit giant isothermal magnetic entropy change (& UDelta;S-M) across their induced first-order coupled magnetostructural transition (MST) in the vicinity of room temperature, though in most of the cases, the use of Maxwell relation from a very frequently used but incorrect measurement protocol provides a nonphysical spike to the calculated & UDelta;S-M. Herein, to realize the accurate measurement protocol, we explore magnetocaloric properties of a (FeCoGa)(x) doped (MnNiSi)(1-)(x) compound with x = 0.165 rigorously. Several methods, including the estimation of & UDelta;S-M using Maxwell relation, Clausius-Clapeyron equation, and also from the calorimetry measurement, are discussed explicitly. The studied material is observed to show a MST at 265 K and a giant & UDelta;S-M as large as about -29.3 J kg(-1 )K(-1) due to a magnetic field change of 5 T following the Maxwell equation during discontinuous cooling and field increasing mode, which enables the material as a promising candidate for magnetic refrigeration.

Automated summary

This study investigates the magnetocaloric properties of a (FeCoGa)(x) doped (MnNiSi)(1-)(x) compound with x = 0.165, demonstrating a magnetostructural transition at 265 K and a large isothermal magnetic entropy change of about -29.3 J kg(-1)K(-1) due to a 5 T magnetic field change. This material shows promising potential for magnetic refrigeration.