Carbon nanowalls as material for electrochemical transducers

Abstract

International audienceThe electrochemical reactivity of a carbon nanowalls electrode was highlighted. The carbon nanowalls were synthesized at 520 degrees C in an acetylene/ammonia electron cyclotronic resonance plasma without any metal catalyst. The electrode surface was characterized by scanning and transmission electron microscopy. Its electrochemical reactivity was studied by both cyclic voltammetry and electrochemical impedance spectroscopy. After the carbon nanowalls deposition, the electronic transfer rate constant and the electroactive surface area were found to be increased by a factor of 7 and 3, respectively

Morphology, Microstructure, and Hydrogen Content of Carbon Nanostructures Obtained by PECVD at Various Temperatures

“…It opened a new window to quantum Hall effect, solar cells, biosensors, and electrodes for energy storage devices [7]. Many of the recent studies were devoted to vertically oriented nanosheets or carbon nanowall (CNW) materials, described as graphene sheets forming a self-supported network of vertical wall structures, randomly oriented, with thicknesses of a few tens of nanometers [8].…”

Response to “Comment on ‘Carbon nanowalls as material for electrochemical tranducers’ ” [Appl. Phys. Lett. 96 126102 (2010)]

“…Assuming that only the variable is R ct , we confirm that the values of k°e stimated for the a-C and CNW electrodes were 1.3 ϫ 10 −3 and 9.0ϫ 10 −3 cm s −1 , as reported in our paper. 2 In his comments, Eftekhari 1 was confusing R ct with the sum ͑R ct + R s ͒; the values of 200 and 60 ⍀ obtained from impedance spectroscopy curves correspond to the sum of R ct + R s . The correct R ct should be obtained by subtracting the R s values from 60 and 200.…”

“…Lett Eftekhari published a letter 1 commenting on our paper entitled "Carbon nanowalls as material for electrochemical tranducers." 2 We appreciate his interest in our work and would like to respond to his concerns. This response gives us the opportunity to comment again our results and to clarify some points of his comments due to a misunderstanding and a misreading of our electrochemical investigations.…”

Comment on “Carbon nanowalls as material for electrochemical transducers” [Appl. Phys. Lett. 95, 014104 (2009)]

“…In a Letter by Lauis et al, 1 carbon nanowalls were synthesized with a new approach without the presence of any metallic catalyst. Due to the absence of metallic impurities, it has been claimed that this nanomaterial is useful for electrochemical transducers.…”