Department of Chemistry and Biochemistry, University of Maryland, College Park, Maryland 20742, USA.
Phys Chem Chem Phys. 2011 Sep 7;13(33):15221-6. doi: 10.1039/c1cp21815h. Epub 2011 Jul 20.
MnO(2)/TiN nanotubes are fabricated using facile deposition techniques to maximize the surface area of the electroactive material for use in electrochemical capacitors. Atomic layer deposition is used to deposit conformal nanotubes within an anodic aluminium oxide template. After template removal, the inner and outer surfaces of the TiN nanotubes are exposed for electrochemical deposition of manganese oxide. Electron microscopy shows that the MnO(2) is deposited on both the inside and outside of TiN nanotubes, forming the MnO(2)/TiN nanotubes. Cyclic voltammetry and galvanostatic charge-discharge curves are used to characterize the electrochemical properties of the MnO(2)/TiN nanotubes. Due to the close proximity of MnO(2) with the highly conductive TiN as well as the overall high surface area, the nanotubes show very high specific capacitance (662 F g(-1) reported at 45 A g(-1)) as a supercapacitor electrode material. The highly conductive and mechanically stable TiN greatly enhances the flow of electrons to the MnO(2) material, while the high aspect ratio nanostructure of TiN creates a large surface area for short diffusion paths for cations thus improving high power. Combining the favourable structural, electrical and energy properties of MnO(2) and TiN into one system allows for a promising electrode material for supercapacitors.
MnO(2)/TiN 纳米管是使用简便的沉积技术制造的，以最大限度地提高用于电化学电容器的电活性材料的表面积。原子层沉积用于在阳极氧化铝模板内沉积共形纳米管。模板去除后，TiN 纳米管的内外表面暴露出来，用于电化学沉积氧化锰。电子显微镜显示，MnO(2)沉积在 TiN 纳米管的内外表面，形成 MnO(2)/TiN 纳米管。循环伏安法和恒电流充放电曲线用于表征 MnO(2)/TiN 纳米管的电化学性能。由于 MnO(2)与高导电性 TiN 的紧密接近以及整体高表面积，纳米管作为超级电容器电极材料表现出非常高的比电容（在 45 A g(-1)下报告为 662 F g(-1)）。高导电性和机械稳定的 TiN 极大地增强了电子流向 MnO(2)材料的流动，而 TiN 的高纵横比纳米结构为阳离子的短扩散路径创造了大表面积，从而提高了高功率。将 MnO(2)和 TiN 的有利结构、电学和能量特性结合到一个系统中，为超级电容器提供了一种有前途的电极材料。
