Realizing half-metallicity in KCoF exfoliated nanosheets defect engineering

• Published in: Physical chemistry chemical physics : PCCP Vol. 18; no. 23; pp. 15765 - 15773
• Main Authors: Bai, Yujie, Deng, Kaiming, Kan, Erjun
• Format: Journal Article
• Published: 08.06.2016
• ISSN: 1463-9076; 1463-9084
• DOI: 10.1039/c6cp02362b

Two-dimensional (2D) materials with intriguing electronic characteristics open up tremendous opportunities for application in future nanoelectronic devices, and have become one of the hot subjects of today's research. Here, we firstly predict the possibility of realizing a 2D exfoliated ionic bonding nanosheet, namely the K 2 CoF 4 nanosheet, based on first-principles calculations. Through analysis of the cleavage energy, in-plane stiffness and stability, the free-standing K 2 CoF 4 nanosheet can be exfoliated in experiments. It is shown that the K 2 CoF 4 nanosheet with K vacancy can transform into a ferromagnetic half-metal under moderate tensile strain, whereas the pristine K 2 CoF 4 nanosheet is an antiferromagnetic semiconductor. Monte Carlo simulations based on the Heisenberg model predict that the Curie temperature for the K vacancy K 2 CoF 4 nanosheet under 2% tensile strain is higher than room temperature. Therefore, our results suggest that the K 2 CoF 4 nanosheet may be a promising material for spintronic and nanoelectronic applications. We explored the possibility of realizing a 2D exfoliated ionic bonding nanosheet, and investigated its electronic and magnetic properties.