Liu Xiaobiao, Tan Jie, Wang Aizhu, Zhang Xiaoming, Zhao Mingwen
School of Physics and State Key Laboratory of Crystal Materials, Shandong University, Jinan, Shandong 250100, China.
Phys Chem Chem Phys. 2014 Nov 14;16(42):23286-91. doi: 10.1039/c4cp03478c.
Covalent organic frameworks (COFs) hold great promise in several applications, such as sieves, catalytic supports and gas storage because of their unique structures and electronic properties. However, most of these metal-free COFs are nonmagnetic and cannot be directly used in spintronics. Here, based on first-principles calculations, we predict that substitutional doping of COF-5 with nitrogen and boron atoms can modify the electronic structures, inducing stable electron spin-polarization in the framework. The preferability of the different doping sites is checked. The electronic structures of the doped COF-5 are dependent on the doping sites and doping atoms, which offer high degrees of freedom to tune the electronic properties. Kagome lattices of S = 1/2 spins can be achieved in the COF-5, suggesting a promising candidate for spin-liquid materials.
共价有机框架（COFs）由于其独特的结构和电子性质，在诸如筛网、催化载体和气体存储等多种应用中具有巨大潜力。然而，这些无金属的COFs大多是非磁性的，不能直接用于自旋电子学。在此，基于第一性原理计算，我们预测用氮原子和硼原子对COF-5进行取代掺杂可以改变其电子结构，在框架中诱导出稳定的电子自旋极化。我们检查了不同掺杂位点的优先性。掺杂后的COF-5的电子结构取决于掺杂位点和掺杂原子，这为调节电子性质提供了高度的自由度。在COF-5中可以实现S = 1/2自旋的 Kagome晶格，这表明它是自旋液体材料的一个有前景的候选者。
