Santoy-Flores Raúl, Fernández-Escamilla Héctor Noe, Páez-Ornelas José Israel, Perez-Tijerina Eduardo G, Guerrero-Sánchez Jonathan, Ponce-Pérez Rodrigo, Takeuchi Noboru, Moreno-Armenta Ma Guadalupe
Facultad de Ciencias Físico-Matemáticas, Universidad Autónoma de Nuevo León, Código Postal, San Nicolás de los Garza, Nuevo León 66451, Mexico.
Centro de Nanociencias y Nanotecnología, Universidad Nacional Autónoma de México, Apartado Postal 14, Código Postal, Ensenada, Baja California 22800, Mexico.
ACS Omega. 2024 Jun 21;9(26):28903-28911. doi: 10.1021/acsomega.4c03603. eCollection 2024 Jul 2.
The new generation of Li-ion batteries is based on integrating 2D materials into the electrodes to increase the energy density while reducing the charging time and size. The two-dimensional transition metal carbide or nitride (MXene) materials offer ideal electronic properties, such as metallic behavior, low energy barriers for Li-ion diffusion, and structural stability. This study focuses on NbC and NbCO MXenes, which have shown promising Li-storage capacity, especially the oxidized phase. By using density functional theory (DFT) and thermodynamic criteria, we studied the Li intercalation process in both MXenes. The results show that the Li intercalation process in the oxidized phase is more stable. Also, the Li diffusion barriers are 35 and 250 meV for the bare and oxidized phase, due to the strong interaction between Li ions and O functional groups. NbC and NbCO MXenes deliver a maximum gravimetric theoretical capacity of 275 and 233.26 mA h/g, respectively, with a stable performance.
新一代锂离子电池基于将二维材料集成到电极中，以提高能量密度，同时缩短充电时间并减小尺寸。二维过渡金属碳化物或氮化物（MXene）材料具有理想的电子特性，如金属行为、锂离子扩散的低能垒以及结构稳定性。本研究聚焦于NbC和NbCO MXene，它们已展现出有前景的锂存储容量，尤其是氧化相。通过使用密度泛函理论（DFT）和热力学标准，我们研究了两种MXene中的锂嵌入过程。结果表明，氧化相中的锂嵌入过程更稳定。此外，由于锂离子与O官能团之间的强相互作用，裸相和氧化相的锂扩散势垒分别为35和250毫电子伏特。NbC和NbCO MXene分别具有275和233.26毫安时/克的最大理论比容量，且性能稳定。
