In the recent past, beryllium–boron compounds have been the focus of attention as a consequence of their extremely rich structures and potential applications. Nevertheless, their complex phase structures greatly hinder further exploration of the physical and chemical properties. To this end, we propose a novel beryllium–boron compound based on a two-dimensional (2D) structure, namely a Be₂B₂ monolayer. Using first-principles methods, we first prove that the structure of the 2D Be₂B₂ monolayer is energetically and thermodynamically stable. Subsequently, we systematically explored its potential as a high performance anode material for LIBs and NIBs. The results reveal that the Be₂B₂ monolayer exhibits an excellent, comprehensive performance with a strong adsorption energy, low diffusion barrier, suitable average open circuit voltage and outstanding electronic conductivity. More importantly, the extremely high theoretical specific capacity (1352 mA h g⁻¹ for both LIBs and NIBs) well meets our expectations, which is quite ideal for an anode material. Meanwhile, we hope and believe that this work can provide some new insights into the study of beryllium–boron compounds.

中文翻译：

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Be2B2 单层的预测：用于锂离子和钠离子电池的超高容量负极材料

近年来，铍-硼化合物因其极其丰富的结构和潜在的应用而成为人们关注的焦点。然而，它们复杂的相结构极大地阻碍了对物理和化学性质的进一步探索。为此，我们提出了一种基于二维（2D）结构的新型铍-硼化合物，即Be ₂ B ₂单层。使用第一性原理方法，我们首先证明了二维 Be ₂ B ₂单分子层的结构在能量和热力学上是稳定的。随后，我们系统地探索了其作为 LIBs 和 NIBs 高性能负极材料的潜力。结果表明，Be ₂ B ₂单层具有优异的综合性能，具有很强的吸附能、低扩散势垒、合适的平均开路电压和出色的电子导电性。更重要的是，极高的理论比容量（LIB 和 NIB 均为 1352 mA hg ^-1）很好地满足了我们的预期，这对于负极材料来说是非常理想的。同时，我们希望并相信这项工作可以为铍-硼化合物的研究提供一些新的见解。