Pulsed anodic arc discharge for the synthesis of carbon nanomaterials

Abstract

Pulsed arc discharges can improve arc control and tailor the ablation process in the production of 1D and 2D nanostructures from carbon anodes. In this work, low-dimensional carbon nanoparticles have been generated by means of anodic arc discharge in helium atmosphere excited with a square-wave modulated signal (1-5 Hz, 10% duty cycle). The discharges were performed between two graphite electrodes with maximal peak current of 250 A and maximal voltage of 65 V. The erosion rates and conversion efficiency of the ablated anode are compared to reference samples grown in DC steady arc mode. Ablation rates in pulsed arcs are typically of the order of 1 mg s −1 . Combination of fast Langmuir probe diagnostics and optical emission spectroscopy provided plasma parameters of the discharges at the arc column. Ranges of 10 16 -10 17 m −3 for electron density and 0.5-2.0 eV for electron temperature are estimated. The obtained samples were characterized with Raman spectroscopy and scanning electron microscopy. The deposit on the cathode after pulsed arc consisted of carbon nanostructures such as graphene nano-platelets and carbon nanotubes. Erosion dynamics of pulsed arc discharge has been described in terms of a global model and compared to steady arc discharge. A correlation is identified among discharge regimes, optical emission patterns and ablation modes. In conclusion, pulsed anodic arc discharge is a very efficient source of carbon nanomaterials. The large control of the discharge characteristics will permit to tailor accurately the production and the properties of carbon nanotubes and graphene. This deposition method is promising for the fabrication of semiconducting nanomaterials with tuneable electrical and optical properties.

Reverse battery model for anodic arc discharges near atmospheric pressure

“…The anodic arc discharges were performed with an experimental setup described elsewhere [10,14]. Briefly, the discharges were sustained between two vertically aligned electrodes installed in a cylindrical stainless steel chamber, whose volume is 4500 cm 3 .…”

“…The development and improvement of said model should provide an approximate picture of the basic dynamics of plasma bulk and plasma sheaths in front of periodic variations of arc signals (current and voltage). To the best of our knowledge, a 1D modelling approach of pulsed arc discharges with elementary circuit elements has not been reported yet, in part due to the novelty of such method [10]. All the aforementioned factors justify the convenience of the present study on electrical plasma parameters within the framework of atmospheric arc discharges.…”

“…Such discharges have been recently introduced by Corbella et al [10]. Their performance addresses issues of arc instability and powder formation [11][12][13].…”

Review of Graphene in Cathode Materials for Lithium-Ion Batteries

“…Up to the present, the preparation methods of graphene can be roughly divided into physical and chemical methods. Among them, physical methods include the micromechanical stripping method, epitaxial growth method, − and arc discharge method, − and the chemical methods include the GO reduction method, carbon nanotube axial cutting method, and CVD method.…”

Engineering of Hydrogenated (6,0) Single-Walled Carbon Nanotube under Applied Uniaxial Stress: A DFT-1/2 and Molecular Dynamics Study

“…They are categorized into three methods depending upon the experimental conditions viz. (a) laser-ablation method − (b) arc-discharge, − and (c) thermal chemical vapor deposition method. , Laser-ablation method gives high-quality and high-purity nanotubes, but the cost of production is high. The most cost-efficient method is the arc-discharge method.…”