Carrier-Induced\nRoom-Temperature Half-Metallicity\nin an Exfoliable Two-Dimensional Cr(TCNB)<sub>2</sub> Metal–Organic\nFramework

Half-metallicity, enabling 100% spin polarization, is\npivotal for\nspintronics but remains challenging to achieve in low-dimensional\nmaterials. Using first-principles calculations, we theoretically propose\nan experimentally feasible two-dimensional (2D) metal–organic\nframework (MOF) magnetic semiconductor, Cr(TCNB)<sub>2</sub> (TCNB\n= 1,2,4,5-tetracyanobenzene). This monolayer can be exfoliated from\na Ag(100) substrate due to its low exfoliation energy of 0.14 J/m<sup>2</sup>. Phonon spectra and ab initio molecular dynamics confirm\nits dynamical and thermal stability up to 600 K. Cr(TCNB)<sub>2</sub> exhibits a ferrimagnetic ground state stabilized by direct <i>p</i>–<i>d</i> magnetic interactions. Notably,\ncarrier doping induces half-metallicity, transforming it into a fully\nspin-polarized conductor. Monte Carlo simulation predicts that doping\nelevates the Curie temperature above room temperature. This work introduces\na novel 2D MOF magnet with carrier-tunable half-metallicity, offering\npromising potential for flexible and nanoscale spintronic devices.