Ion Intercalation into Two-Dimensional Transition-Metal Carbides: Global Screening for New High-Capacity Battery Materials
Ion Intercalation into Two-Dimensional Transition-Metal Carbides: Global Screening for New High-Capacity Battery Materials
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DOI：
10.1021/ja508154e
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发表时间：
2014-11-19
影响因子：
15
通讯作者：
Islam, M. Saiful
中科院分区：
文献类型：
--
作者：
Eames, Christopher;Islam, M. Saiful
二维过渡金属碳化物（简称MXene）是一类新型化合物，由于其独特的性质和潜在的应用前景而引起人们的极大兴趣。最近已经证明离子嵌入MXene具有良好的电化学性能，使其成为可充电电池的可行电极材料。在这里，我们已经进行了全球筛选的容量和电压的各种嵌入离子（Li+，Na+，K+，和Mg2+）到大量的M2C基化合物（M = Sc，Ti，V，Cr，Zr，Nb，Mo，Hf，Ta）与F-，H-，O-，OH-功能化的表面，使用密度泛函理论方法。就重量容量而言，与Na+或Kt相比，更大量的Lit或Mg2+可以嵌入MXene中，这与嵌入离子的尺寸有关。表面官能团和过渡金属物种的变化会显着影响MXene的电压和容量，其中氧终止导致最高容量。在阳极电压和重量容量（> 400 mAh/g）方面最有前途的M2C材料组是含有轻过渡金属的化合物（例如，Sc、Ti、V和Cr），其具有非官能化或O-封端的表面。本文提供的结果为探索用于潜在电池应用的各种高容量MXene提供了有价值的见解。
Two-dimensional transition metal carbides (termed MXenes) are a new family of compounds generating considerable interest due to their unique properties and potential applications. Intercalation of ions into MXenes has recently been demonstrated with good electro-chemical performance, making them viable electrode materials for rechargeable batteries. Here we have performed global screening of the capacity and voltage for a variety of intercalation ions (Li+, Na+, K+, and Mg2+) into a large number of M2C-based compounds (M = Sc, Ti, V, Cr, Zr, Nb, Mo, Hf, Ta) with F-, H-, O-, and OH-functionalized surfaces using density functional theory methods. In terms of gravimetric capacity a greater amount of Lit or Mg2+ can be intercalated into an MXene than Na+ or Kt, which is related to the size of the intercalating ion. Variation of the surface functional group and transition metal species can significantly affect the voltage and capacity of an MXene, with oxygen termination leading to the highest capacity. The most promising group of M2C materials in terms of anode voltage and gravimetric capacity (>400 mAh/g) are compounds containing light transition metals (e.g., Sc, Ti, V, and Cr) with nonfunctionalized or O-terminated surfaces. The results presented here provide valuable insights into exploring a rich variety of high-capacity MXenes for potential battery applications.