Synthesis and Characterization of 2D Molybdenum Carbide (MXene)

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• 作者：Joseph Halim ; Sankalp Kota ; Maria R. Lukatskaya ; Michael Naguib ; Meng-Qiang Zhao ; Eun Ju Moon ; Jeremy Pitock ; Jagjit Nanda ; Steven J. May ; Yury Gogotsi and Michel W. Barsoum
• 刊名：Advanced Functional Materials
• 出版年：2016
• 出版时间：May 10, 2016
• 年：2016
• 卷：26
• 期：18
• 页码：3118-3127
• 全文大小：1735K
• ISSN：1616-3028

文摘

Large scale synthesis and delamination of 2D Mo₂CT _x (where T is a surface termination group) has been achieved by selectively etching gallium from the recently discovered nanolaminated, ternary transition metal carbide Mo₂Ga₂C. Different synthesis and delamination routes result in different flake morphologies. The resistivity of free-standing Mo₂CT _x films increases by an order of magnitude as the temperature is reduced from 300 to 10 K, suggesting semiconductor-like behavior of this MXene, in contrast to Ti₃C₂T _x which exhibits metallic behavior. At 10 K, the magnetoresistance is positive. Additionally, changes in electronic transport are observed upon annealing of the films. When 2 μm thick films are tested as electrodes in supercapacitors, capacitances as high as 700 F cm⁻³ in a 1 m sulfuric acid electrolyte and high capacity retention for at least 10,000 cycles at 10 A g⁻¹ are obtained. Free-standing Mo₂CT _x films, with ≈8 wt% carbon nanotubes, perform well when tested as an electrode material for Li-ions, especially at high rates. At 20 and 131 C cycling rates, stable reversible capacities of 250 and 76 mAh g⁻¹, respectively, are achieved for over 1000 cycles.