Department of Chemistry, Seoul National University, Seoul, Korea.
Phys Chem Chem Phys. 2012 Jan 14;14(2):448-63. doi: 10.1039/c1cp22927c. Epub 2011 Nov 28.
Physical and electrochemical features of nanoporous electrodes arising from their morphology are presented in this perspective. Although nanoporous electrodes have been used to enhance electrocatalysis for several decades, the origin of their capability was understood on the basis of enlarged surface area or crystalline facet. However, considerable attention should be paid to the fact that nano-confined space of nanoporous electrodes can significantly affect electrochemical efficiency. Molecular dynamics in nano-confined spaces is capable of offering much more chances of interaction between a redox molecule and an electrode surface. The mass transport in the nanoporous electrode depends on various pore characteristics such as size, shape, charge, connectivity, and symmetry as well as molecular properties such as size, charge, and kinetics. Moreover, when the pore size is comparable to the thickness of an electric double layer (EDL), the EDLs overlap in the porous structure so that electrochemically effective surface area is not the same as that of the real electrode surface. These unique properties come from simply nanoporous structure and suggest new opportunity to innovative electrocatalysts in the future.
本文从形态学角度介绍了源于纳米多孔电极的物理和电化学特性。尽管纳米多孔电极已经被用于增强电催化作用几十年，但它们的能力起源是基于增大的表面积或晶体面来理解的。然而，人们应该注意到这样一个事实，即纳米多孔电极的纳米受限空间可以显著影响电化学效率。纳米受限空间中的分子动力学能够为氧化还原分子与电极表面之间的相互作用提供更多机会。纳米多孔电极中的质量传输取决于各种孔特征，如尺寸、形状、电荷、连通性和对称性，以及分子特性，如大小、电荷和动力学。此外，当孔径与双电层（EDL）的厚度相当时，多孔结构中的 EDL 会重叠，使得电化学有效表面积与实际电极表面积不同。这些独特的性质源于简单的纳米多孔结构，并为未来创新的电催化剂提供了新的机会。
