Ultralow Interlayer Friction of Layered Electride Ca<sub>2</sub>N: A Potential Two-Dimensional Solid Lubricant Material
Jianjun Wang,
Lin Li,
Ziting Shen,
Peng Guo,
Meng Li,
Bin Zhao,
Lili Fang,
Linfeng Yang
Affiliations
Jianjun Wang
Computational and Design Center for Low-dimensional Quantum Material, and College of Science, Zhongyuan University of Technology, Zhengzhou 450007, China
Lin Li
Delivery Devices and Connected Solutions, Eli Lilly and Company, Indianapolis, IN 46285, USA
Ziting Shen
Computational and Design Center for Low-dimensional Quantum Material, and College of Science, Zhongyuan University of Technology, Zhengzhou 450007, China
Peng Guo
Computational and Design Center for Low-dimensional Quantum Material, and College of Science, Zhongyuan University of Technology, Zhengzhou 450007, China
Meng Li
Computational and Design Center for Low-dimensional Quantum Material, and College of Science, Zhongyuan University of Technology, Zhengzhou 450007, China
Bin Zhao
Computational and Design Center for Low-dimensional Quantum Material, and College of Science, Zhongyuan University of Technology, Zhengzhou 450007, China
Lili Fang
Computational and Design Center for Low-dimensional Quantum Material, and College of Science, Zhongyuan University of Technology, Zhengzhou 450007, China
Linfeng Yang
Computational and Design Center for Low-dimensional Quantum Material, and College of Science, Zhongyuan University of Technology, Zhengzhou 450007, China
Dispersion-corrected density functional theory (DFT) calculations reveal that the layered electride of dicalcium nitride (Ca2N) exhibits stronger interlayer binding interactions but lower interlayer friction behavior than that of traditional layered lubricants weakly bonded by van der Waals (vdW) interactions, such as graphite, h-BN, and MoS2. These results are attributed to the two-dimensional (2D) homogeneous conduction electrons distribution in the middle of the interlayer space of Ca2N, which yields a smooth sliding barrier and hence ultralow friction behavior. The interesting results obtained in this study have not only broadened the scope of 2D solid lubricants but also enriched the physical understanding of ultralow friction mechanism for 2D systems.
