Carrier-Induced Room-Temperature Half-Metallicity in an Exfoliable Two-Dimensional Cr(TCNB)2 Metal-Organic Framework
Yangqi Ji1, Haifeng Lv1, Xiaojun Wu1
1Key Laboratory of Precision and Intelligent Chemistry, School of Chemistry and Materials Science, CAS Key Laboratory of Materials for Energy Conversion, CAS Center for Excellence in Nanoscience, University of Science and Technology of China, Hefei, Anhui 230026, P.R. China.
Abstract:
Half-metallicity, enabling 100% spin polarization, is pivotal for spintronics but remains challenging to achieve in low-dimensional materials. Using first-principles calculations, we theoretically propose an experimentally feasible two-dimensional (2D) metal-organic framework (MOF) magnetic semiconductor, Cr(TCNB)2 (TCNB = 1,2,4,5-tetracyanobenzene). This monolayer can be exfoliated from a Ag(100) substrate due to its low exfoliation energy of 0.14 J/m2. Phonon spectra and ab initio molecular dynamics confirm its dynamical and thermal stability up to 600 K. Cr(TCNB)2 exhibits a ferrimagnetic ground state stabilized by direct p-d magnetic interactions. Notably, carrier doping induces half-metallicity, transforming it into a fully spin-polarized conductor. Monte Carlo simulation predicts that doping elevates the Curie temperature above room temperature. This work introduces a novel 2D MOF magnet with carrier-tunable half-metallicity, offering promising potential for flexible and nanoscale spintronic devices.
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