Tan Hao, Wang Chao, Duan Hengli, Tian Jie, Ji Qianqian, Lu Ying, Hu Fengchun, Hu Wei, Li Guinan, Li Na, Wang Yao, Chu Wangsheng, Sun Zhihu, Yan Wensheng
National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei 230029, P. R. China.
Engineering and Materials Science Experiment Center, University of Science and Technology of China, Hefei 230029, P. R. China.
ACS Appl Mater Interfaces. 2021 Jul 21;13(28):33363-33370. doi: 10.1021/acsami.1c07906. Epub 2021 Jul 8.
Two-dimensional (2D) materials with intrinsic magnetic properties are intensively explored due to their potential applications in low-power-consumption electronics and spintronics. To date, only a handful of intrinsic magnetic 2D materials have been reported. Here, we report a realization of intrinsic ferromagnetic behavior in 2D VC MXene nanosheets through layer mismatch engineering. The VC MXene nanosheets with a small-angle twisting show a robust intrinsic ferromagnetic response with a saturation magnetic moment of 0.013 emu/g at room temperature. An in-depth study has been performed by X-ray absorption spectroscopy as well as electron paramagnetic resonance (EPR) and photoelectron spectroscopy analyses. It has been revealed that the symmetry-broken interlayer twisting reduced the degeneracy of V 3d states and the van Hove singularity. This led to a redistribution of the density of electronic states near the Fermi level and consequently activated the Stoner ferromagnetism with improved density of itinerant d electrons. This work highlights VC MXene as a promising intrinsic room-temperature ferromagnetic material with potential applications in spintronics or spin-based electronics.
具有本征磁性的二维（2D）材料因其在低功耗电子学和自旋电子学中的潜在应用而受到广泛研究。迄今为止，仅报道了少数几种本征磁性二维材料。在此，我们通过层错配工程实现了二维VC MXene纳米片中的本征铁磁行为。具有小角度扭曲的VC MXene纳米片在室温下表现出强大的本征铁磁响应，饱和磁矩为0.013 emu/g。通过X射线吸收光谱以及电子顺磁共振（EPR）和光电子能谱分析进行了深入研究。结果表明，对称性破缺的层间扭曲降低了V 3d态的简并度和范霍夫奇点。这导致费米能级附近电子态密度的重新分布，从而激活了具有改善的巡游d电子密度的斯托纳铁磁性。这项工作突出了VC MXene作为一种有前途的本征室温铁磁材料，在自旋电子学或基于自旋的电子学中具有潜在应用。
