Electrochimica Acta, Vol.55, No.1, 68-77, 2009
Electron transfer across a conducting nanowire (nanotube)/electrolyte solution interface
The reduction of anions (considering hexacyanoferrate (III) as example) at charged conducting cylinders of nano-size, i.e., metal wires or carbon tubes, in contact with electrolyte solution is explored over a wide range of overpotentials. Two key parameters contributing to the current (solvent reorganization energy and work terms) are addressed in the framework of a quantum mechanical theory of electron transfer. It is argued that double layer effects play a crucial role and entail a significant rise of the current density as compared with plain metal electrodes. The stationary diffusion to a nanocylinder was found to proceed much faster, which results in an additional enhancement of the current. Some qualitative effects of the electron transfer across a conducting nanocylinder are discussed (in part, the appearance of an inverted Arrhenius plot). (C) 2009 Elsevier Ltd. All rights reserved.
Keywords:Metal nanowire;Carbon nanotube;Heterogeneous electron transfer;Hexacyanoferrate;Electrical double layer;Solvent reorganization energy