New concepts in molecular and energy transport within carbon nanotubes: Thermopower waves and stochastically resonant ion channels

Research areas:
  • Uncategorized
Year: 2011
Type of Publication: Article
  • Steven Shimizu, Joel T. Abrahamson Wonjoon Choi
Journal: Physica Status Solidi B-Basic Solid State Physics Volume: 248
Number: 11 Pages: 2445-2448
Month: NOV 2011
PT: J; TC: 0; UT: WOS:000297517100003
Our laboratory has been interested in how carbon nanotubes can be utilized to illustrate new concepts in molecular and energy transfer. In the first example, we predict and demonstrate the concept of thermopower waves for energy generation. Coupling an exothermic chemical reaction with a thermally conductive CNT creates a self-propagating reactive wave driven along its length. We realize such waves in multi-walled nanotubes (MWNT) and show that they produce concomitant electrical pulses of high specific power >7 kW/kg. Such waves of high power density may find uses as unique energy sources. In the second system, we fabricate and study single-walled nanotube (SWNT) ion channels for the first time and show that the longest, highest aspect ratio, and smallest diameter synthetic nanopore examined to date, a 500 mu m SWNT, demonstrates oscillations in electro-osmotic current at specific ranges of electric field, that are the signatures of coherence resonance, yielding self-generated rhythmic and frequency-locked transport. The observed oscillations in the current occur due to a coupling between stochastic pore blocking and a diffusion limitation that develops at the pore mouth during proton transport. (C) 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim