A sign of field-induced first order magnetic state transition and giant reversible magnetocaloric effect in cobalt hydroxide nanosheets

Authors

Precious Shamba, University of WollongongFollow
Rong Zeng, University of WollongongFollow
J Q Wang, University of Jinan, China
S X. Dou, University of WollongongFollow

RIS ID

32937

Publication Details

Shamba, P, Zeng, R, Wang, JQ, & Dou, SX (2010), A sign of field-induced first order magnetic state transition and giant reversible magnetocaloric effect in cobalt hydroxide nanosheets, Journal of Applied Physics, 107(9), pp. 1-3.

Abstract

We report the synthesis of β−Co(OH)₂ nanosheets using microwave assisted hydrothermal and conventional chemical reaction methods. A magnetic transition at an onset temperature, T₁ ~ 96 K, and a sign of antiferromagnetic state transition at the Néel temperature, T_N=9~10 K, can be determined from M-T curves and M-H curves magnetic properties investigation. It is found that a sign of field-induced first order transition below 9 K, act as a role of reversing the magnetocaloric effect from negative to positive value. The large reversible magnetic-entropy change (∆S_M) of 17 J/kg K around 11 K for a field change of 5 T indicates that this material is useful for refrigeration applications at low temperatures.

Grant Number

ARC/DP0879070

Additional Grant Number

http://purl.org/au-research/grants/ARC/DP0879070