伪电容性贡献用于在高度排序的V组中孔性过渡金属氧化物中储存电荷,具有面向异位的分层纳米晶体域
Kirstin Brezesinski1, John Wang, Jan Haetge
1Institute of Physical Chemistry, Justus-Liebig-University Giessen, Heinrich-Buff-Ring 58, 35392 Giessen, Germany.
Journal of the American Chemical Society
|May 4, 2010
概括
使用块共聚合物合成了高度排序的中孔性过渡金属氧化物薄膜. 这些材料具有优越的电化学性能,可用于储能应用.
科学领域:
- 材料科学 材料科学 材料科学
- 纳米技术 纳米技术
- 电化学 电化学 电化学
背景情况:
- 两类块共聚物作为有效的模板,用于创建周期性无机纳米结构.
- 对于先进的应用来说,开发具有控制的晶体学方向的有序等孔材料至关重要.
研究的目的:
- 为了合成和表征高度有序的中孔氧化 (TaNbO5),氧化 (Nb2O5) 和氧化 (Ta2O5) 薄膜.
- 研究这些新型半孔材料的电化学特性,特别是伪电容性电荷存储.
主要方法:
- 无机sol-gel前体与聚乙烯-co-butylene-b-poly (乙烯氧化物) 双块共聚合物 (KLE) 的联合组装.
- 热处理以诱导结晶并形成有序的立方孔-固体结构.
- 在各种基板上结晶学对齐和中孔结构的表征.
主要成果:
- 成功地制造出具有高度结晶性的T-Nb2O5,L-Ta2O5和TaNbO5半孔薄膜,具有有序的立方孔固体结构.
- 在多种基质上实现了高晶体对齐,克服了传统表皮质的局限性.
- 与无形对应物相比,半孔Nb2O5薄膜显示出明显增强的伪容量电荷存储.
结论:
- 合成方法可以生产具有可调节性质的定向半孔过渡金属氧化物.
- 中等度和晶体学定向的独特组合显著提高了电化学性能,特别是间隙伪电容.
- 这些材料对高性能储能设备具有前景.
相关概念视频
01:25MOS Capacitor
A Metal-Oxide-Semiconductor (MOS) capacitor is a fundamental structure used extensively in semiconductor device technology, particularly in the fabrication of integrated circuits and MOSFETs (metal-oxide-semiconductor field-effect transistors). The MOS capacitor consists of three layers: a metal gate, a dielectric oxide, and a semiconductor substrate.
The metal gate is typically made from highly conductive materials such as aluminum or polysilicon. Beneath the metal gate lies a thin layer of...
The metal gate is typically made from highly conductive materials such as aluminum or polysilicon. Beneath the metal gate lies a thin layer of...
01:31Dielectric Polarization in a Capacitor
The presence of a dielectric medium in a capacitor not only changes the voltage and capacitance but also affects the electric field. In general, dielectrics can be of two types: polar and nonpolar. In a polar dielectric, the positive and negative charges in the molecules are separated by a distance and hence have a permanent dipole moment. In contrast, no such charge separation exists in a nonpolar dielectric, however the nonpolar molecules get polarized in the presence of an external electric...
01:26Spherical and Cylindrical Capacitor
A spherical capacitor consists of two concentric conducting spherical shells of radii R1 (inner shell) and R2 (outer shell). The shells have equal and opposite charges of +Q and −Q, respectively. For an isolated conducting spherical capacitor, the radius of the outer shell can be considered to be infinite.
Conventionally, considering the symmetry, the electric field between the concentric shells of a spherical capacitor is directed radially outward. The magnitude of the field, calculated by...
Conventionally, considering the symmetry, the electric field between the concentric shells of a spherical capacitor is directed radially outward. The magnitude of the field, calculated by...
02:37Metallic Solids
Metallic solids such as crystals of copper, aluminum, and iron are formed by metal atoms. The structure of metallic crystals is often described as a uniform distribution of atomic nuclei within a “sea” of delocalized electrons. The atoms within such a metallic solid are held together by a unique force known as metallic bonding that gives rise to many useful and varied bulk properties.
All metallic solids exhibit high thermal and electrical conductivity, metallic luster, and malleability. Many...
All metallic solids exhibit high thermal and electrical conductivity, metallic luster, and malleability. Many...
02:42Valence Bond Theory
Coordination compounds and complexes exhibit different colors, geometries, and magnetic behavior, depending on the metal atom/ion and ligands from which they are composed. In an attempt to explain the bonding and structure of coordination complexes, Linus Pauling proposed the valence bond theory, or VBT, using the concepts of hybridization and the overlapping of the atomic orbitals. According to VBT, the central metal atom or ion (Lewis acid) hybridizes to provide empty orbitals of suitable...
02:42Ionic Crystal Structures
Ionic crystals consist of two or more different kinds of ions that usually have different sizes. The packing of these ions into a crystal structure is more complex than the packing of metal atoms that are the same size.
Most monatomic ions behave as charged spheres, and their attraction for ions of opposite charge is the same in every direction. Consequently, stable structures for ionic compounds result (1) when ions of one charge are surrounded by as many ions as possible of the opposite...
Most monatomic ions behave as charged spheres, and their attraction for ions of opposite charge is the same in every direction. Consequently, stable structures for ionic compounds result (1) when ions of one charge are surrounded by as many ions as possible of the opposite...