마이크로웨이브 졸-겔법을 응용한 극저온 자기냉매용 HoN 분말 합성 및 자기열량효과

• Published in: 대한금속·재료학회지, 54(4) Vol. 54; no. 4; pp. 275 - 282
• Main Authors: 안종빈, Jong Bin Ahn, 김동수, Dongsoo Kim, 윤석영, Seog Young Yoon, 최철진, Chuljin Choi
• Format: Journal Article
• Language: Korean
• Published: 대한금속재료학회 05.04.2016; 대한금속·재료학회
• Subjects: ceramics; chemical synthesis; magnetic properties; magnetocaloric effect; microwave chemistry; thermal analysis; 재료공학
• ISSN: 1738-8228; 2288-8241
• DOI: 10.3365/KJMM.2016.54.4.275

Rare-earth (RE) mono-nitrides can be used as magnetocaloric materials for the magnetic refrigerant for liquefying hydrogen. In this study, holmium nitride (HoN) particles were prepared by sol-gel method with microwave irradiation. HoN particles were successfully synthesized by 2-step heat treatment in N2 atmosphere form gel-type intermediate by microwave irradiation. X-ray diffraction patterns of the synthesized HoN particles exhibited the six sharp peaks in good agreement with each plane of crystallographic structure of HoN. Especially, the synthesized HoN particles reveal a high magnetic entropy change (△Sm) of 36.6 J/kgK in applied field of 5T at 14.2 K which is comparable with those of rare earth mono-nitrides by carbothermic reduction method or plasma arc discharge technique.