PDF(Pubmed)
Abstract：
A new two-dimensional (2D) non-MXene transition metal carbide, Mo3C2, was found using the USPEX code. Comprehensive first-principles calculations show that the Mo3C2 monolayer exhibits thermal, dynamic, and mechanical stability, which can ensure excellent durability in practical applications. The optimized structures of Lix@(3×3)-Mo3C2 (x = 1-36) and Nax@(3×3)-Mo3C2 (x = 1-32) were identified as prospective anode materials. The metallic Mo3C2 sheet exhibits low diffusion barriers of 0.190 eV for Li and 0.118 eV for Na and low average open circuit voltages of 0.31-0.55 V for Li and 0.18-0.48 V for Na. When adsorbing two layers of adatoms, the theoretical energy capacities are 344 and 306 mA h g-1 for Li and Na, respectively, which are comparable to that of commercial graphite. Moreover, the Mo3C2 substrate can maintain structural integrity during the lithiation or sodiation process at high temperature. Considering these features, our proposed Mo3C2 slab is a potential candidate as an anode material for future Li- and Na-ion batteries.
摘要：
一种新的二维（2D）非MXene过渡金属碳化物，Mo3C2是使用USPEX代码找到的。综合第一性原理计算表明，Mo3C2单层表现出热，动态,和机械稳定性，这可以确保在实际应用中优异的耐久性。Lix@（3×3）-Mo3C2（x=1-36）和Nax@（3×3）-Mo3C2（x=1-32）的优化结构被确定为预期的阳极材料。金属Mo3C2片对Li表现出0.190eV的低扩散势垒，对Na表现出0.118eV的低扩散势垒，对Li表现出0.31-0.55V的低平均开路电压，对Na表现出0.18-0.48V的低平均开路电压。当吸附两层吸附原子时，Li和Na的理论能量容量为344和306mAhg-1，分别,与商业石墨相当。此外，Mo3C2衬底可以在高温下的锂化或碱化过程期间保持结构完整性。考虑到这些特点,我们提出的Mo3C2板坯是未来Li和Na离子电池的阳极材料的潜在候选者。
