Cryogenic magnetocaloric effect of cobalt hydroxide nanoparticles embedded in a nonmagnetic polymer matrix. (October 2020)

• Record Type: Journal Article
• Authors: Joseph, Navya; Mannur Illam, Kavya Kizhakkinakath; Bhat, Ruchira Vedavyasa; Veetil, Neethu Edathil; Kaipamangalath, Aswathy; Varma, Manoj Raama; Thomas, Senoy
• Is Part Of: Journal of physics and chemistry of solids. Volume 145(2020)
• Publication Date: 2020-10
• Subjects: Ion-exchange process -- Nanocomposite -- Magnetocaloric effect -- Paramagnetism; Solids -- Periodicals; Solides -- Périodiques; Solids; Periodicals; 530.41
• DOI: 10.1016/j.jpcs.2020.109527
• Languages: English
• ISSNs: 0022-3697

Abstract

Abstract: The present study reports on the appreciable magnetic entropy change observed in hybrid structures of cobalt hydroxide nanoparticles inside a polymer matrix. The preparation of a magnetic composite of cobalt hydroxide nanoparticles lodged in a polymer matrix of sulfonated polystyrene by the method of the ion-exchange mechanism is outlined. The dimensionality introduced by the resin provides constraints to the particle growth, thereby leading to the formation of a nearly homogeneous distribution of particle. The polymer template serves as a stabilizing and isolating agent. The composite nanostructure shows magnetocaloric effect near to the low-temperature zone, with an entropy change of −5 J/kgK at an applied magnetic field of 7 T. Highlights: Ion-exchange mechanism assisted loading of cobalt ions in seralite strong resin cation-120. Subsequent conversion of cobalt ions to cobalt hydroxide to realize cobalt hydroxide-polymer nanocomposite. Composites show a magnetic entropy change of −5 J/kgK at an applied magnetic field of 7 T at 7.5K.