Laser-anodised carbon fibre: Coupled activation and patterning of sensor substrates

Abstract

This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting galley proof before it is published in its final citable form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.A c c e p t e d m a n u s c r i p t The oxidation increases the proportion of oxygen species such as hydroxyl, carbonyl, carboxyl and quinones at the electrode surface [14]. These are well known to influence the wettability, surface reactivity, porosity and conductivity of the electrode [1,7,8,10]. It can also have the beneficial effect of increasing the availability of edge sites as a consequence of exfoliation / fracturing process that can, as with eppg electrodes, serve to increase electrode sensitivity towards particular analytes.Laser patterning of carbon encapsulated composites have been shown to provide a quick and versatile method of producing electrode sensor assemblies but the ability of the laser to positively influence the surface characteristics of the underlying fibre has yet to be evaluated. The adoption of the electrochemical anodisation A c c e p t e d m a n u s c r i p t H.B Ezekiel et al Nottingham Trent University May 20083 approach requires the introduction of a separate/discrete step in the construction of the electrode sensor and it is clear that combining the patterning/activation process would represent a considerable simplification in the development process. In the present investigation, the use of laser ablation as a means of removing protective polymer encapsulants to expose and activate the sensor surface in a single step is assessed. Experimental DetailsElectrochemical measurements were conducted using a µAutolab type III computer controlled potentiostat (Eco-Chemie, Utrecht, The Netherlands) using a three electrode configuration consisting of a glassy carbon working electrode (3mm diameter, BAS Technicol, UK), a platinum wire counter electrode and a 3 M NaCl Ag Electrochemical anodisation of carbon fibres was conducted using the procedures described previously [23,24] and typically involved amperometric oxidation (+2V, 15 minutes) in 0.1M sodium hydroxide solution. Results and DiscussionCarbon fibres were encapsulated within a polyester resin laminate as described in previous work by the authors [23,24]. An electrode window was then created by rastering the laser across a pre-selected area of the polymer-fibre composite. This has the effect of removing the polymer and exposing the fibre which can, in principle, be 4 kinetics at a substrate that is largely basal plane in structure. The voltammogram recorded at the anodised fibre, in contrast, displays a well defined and easily quantifiable oxidation process. The change in profile is dramatic but is in keeping with previous work where electrochemical anodisation...

Ultrasonic exfoliation of carbon fiber: electroanalytical perspectives

“…These have attempted to alter the surface activation, pore size distribution and functionalisation with an extensive array of species [19,20,49]. In almost all cases, surface pre-treatment is critical and these include: chemical oxidation [50], oxygen plasma [14], gamma irradiation [14], spark discharge [51], thermal air oxidation [14,52,53], laser ablation [54] and various electrochemical techniques [55][56][57]. A brief summary of the more recent approaches are highlighted in Table 1.…”

Enhanced interfacial adhesion in carbon fiber/poly (acrylonitrile‐butadiene‐styrene) composite through fiber surface treatment by an emulsion sizing

“…In this picture, curve a is the FTIR spectrum of the desized CF, which seems to be a straight line with few characteristic absorption peaks. Because the virgin CF with a highly crystallized graphitic structure can hardly provide any functional groups or chemical bonds which possess obvious and discernible absorption peaks in FTIR spectrum . As depicted in curve b , on the contrary, there are numerous characteristic absorption peaks in the spectrum of SA‐1 sized CF resulting from the chemical bond‐link vibrations of functional groups supplied by the film former (ABS, NSM and small amounts of OP‐10) of SA‐1.…”

Laser Treated Carbon Composites for the Determination of Suicide Biomarkers: Development of a Forensic Diagnosis Device

“…The laser treatment is a method of electrode anodisation (39). The laser not only increases the surface area of the electrode but enhances the electron transfer by the incorporation of functional groups such as carboxyl and hydroxyl groups onto the electrode surface.…”

“…This can be done using chemical, thermal or electrochemical methods. In the present communication we have sought to utilize laser anodisation as a more convenient method that is chemical free, patternable and more controllable than conventional wet techniques for modifying carbon based substrates (39). The basic rationale has been to develop a disposable electrode detector that could be easily integrated within a conventional HPLC architecture as shown in Scheme 1 The possibility to modify the electrode surface using a direct and controllable strategy to improve the sensitivity and selectivity of the electrode toward specific analytes offers an alternative to current electrode modification methods used for the detection of neurotransmitters.…”