Jiang Jiaxin, Guo Hongyan, Lu Ning
Department of Physics, Anhui Normal University, Wuhu 241000, China.
Nanomaterials (Basel). 2025 Jun 8;15(12):886. doi: 10.3390/nano15120886.
The global energy shortage and the gradual depletion of lithium resources have become increasingly prominent. Improving the energy density of lithium-based secondary batteries and developing other high-performance alkali-metal secondary batteries have become the research focus. In this study, two-dimensional (2D) hexagonal metal borides (-MBenes) are investigated as ordered alkali metal adsorption substrates for alkali-metal-based battery anode materials using density functional theory (DFT). Twelve thermodynamically stable -MBenes are screened out from thirty-three structures, and their excellent stability and metallic electronic characteristics are confirmed. The ordered multilayered growth in alkali metal adsorption is found to depend on two factors: low lattice mismatching and dynamic matching of the work function. In particular, Mg/Al/V-based -MBenes exhibit excellent lithium lattice matching (<3.35% mismatch), enabling layer-by-layer hexagonal (001) Li growth for ≥5 layers. They have ultrahigh lithium capacities (2170-3818 mAh·g), low migration barriers (0.01-0.05 eV), and low voltages (0.003-0.714 V). Mg/Y-based -MBenes enable three Na layers' adsorption with a capacity of 1717/605 mAh·g, and AlB achieves a 472 mAh·g potassium storage capacity, respectively. Due to the orderly multilayered growth mechanism, Mg/Al/V-based -MBenes show great potential as high-safety and ultrahigh-capacity alkali-metal battery anode materials.
全球能源短缺和锂资源的逐渐枯竭日益突出。提高锂基二次电池的能量密度并开发其他高性能碱金属二次电池已成为研究重点。在本研究中，利用密度泛函理论（DFT）研究了二维（2D）六角形金属硼化物（-MBenes）作为碱金属基电池负极材料的有序碱金属吸附基底。从33种结构中筛选出12种热力学稳定的-MBenes，并证实了它们优异的稳定性和金属电子特性。发现碱金属吸附中的有序多层生长取决于两个因素：低晶格失配和功函数的动态匹配。特别是，基于Mg/Al/V的-MBenes表现出优异的锂晶格匹配（失配<3.35%），能够实现≥5层的逐层六角形（001）Li生长。它们具有超高的锂容量（2170-3818 mAh·g）、低迁移势垒（0.01-0.05 eV）和低电压（0.003-0.714 V）。基于Mg/Y的-MBenes能够吸附三层Na，容量分别为1717/605 mAh·g，AlB实现了472 mAh·g的钾存储容量。由于有序的多层生长机制,基于Mg/Al/V的-MBenes作为高安全性和超高容量碱金属电池负极材料具有巨大潜力。
