Electro-catalytic oxidation of cellulose at Au electrode
نویسندگان
چکیده
Cellulose is expected to have a key role in the sustainable society in the future. This natural polysaccharide can be used as alternative raw material to petrochemical products. Cellulose based functional materials can be modified to desired applications by changing their physicochemical properties. Chemical and/or biochemical reactions have so far been used to modify chemical groups on cellulose molecules. It has been assumed that it is difficult to treat the polysaccharides by other than chemical or biochemical method because they are basically insoluble in water and electrochemically inactive. However, dissolution of the polysaccharides in a suitable solvent, which function as an electrolyte would open new research fields such as “electrochemistry of polysaccharides”, as a new horizon to utilization of polysaccharides. In this presentation, the fundamental electrochemical properties of cellulose dissolved in sodium hydroxide solution at Au surface were investigated by cyclic voltammetry (CV), in situ Fourier transform infrared attenuated total reflectance spectroscopy (FTIR-ATR), electrochemical quartz crystal microbalance (EQCM) and electrochemical impedance spectroscopy (EIS). The reaction products were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), and FTIR spectroscopy and nuclear magnetic resonance (NMR). The results imply that cellulose at Au electrode surface in sodium hydroxide solution undergo irreversible oxidation. It is suggested that adsorption and desorption of hydroxide anions at the Au surface during a potential cycle have an important catalytic role in the electrochemical reaction of cellulose at Au electrode (e.g. approach to the electrode surface, electron transfer, adsorption and desorption of the reaction species at the electrode surface). Moreover, it was found that two types of cellulose derivatives were obtained as products of the electrochemical oxidation reaction. One is a water soluble cellulose derivative where some hydroxyl groups are partially oxidized to carboxylic groups. The other derivative is a water insoluble hybrid material composed of cellulose and Au nanoparticles (approx. 4 nm diameter). Furthermore, a reaction scheme of the electro-catalytic oxidation of cellulose at gold electrode in basic medium is proposed (Scheme 1). Scheme 1. Electro-catalytic reaction of cellulose at Au in alkaline medium
منابع مشابه
Electropolymerization of 4-aminobenzoic acid containing nano-Au deposited on carbon paste electrode for determination of acetaminophen
The conducting polymer films have been widely applied in the field of electrochemistry owing to their goodstability, permselectivity, unique physical and chemical properties. A novel nano-Au/poly (4-aminobenzoicacid) (PABA) film modified carbon paste electrode was fabricated for sensitive detection of acetaminophenin this paper. The PABA film and nano-Au/PABA film were characterized by scanning...
متن کاملSurface Modification of Glassy Carbon Electrode by Ni-Cu Nanoparticles as a Competitive Electrode for Ethanol Electro-Oxidation
In the present study, Nickel-Copper nanoparticles were electrodeposited on glassy carbon electrode (GCE) by using electroplating deposition method. The prepared electrode was characterized by scanning electron microscopy (SEM) and elemental mapping analysis. Results showed that Ni-Cu nanoparticles with a high density are distributed at the surface of the glassy carbon electrode. Subsequentl...
متن کاملElectro-Catalytic Oxidation of Methanol at Ni(OH)2 Nanoparticles-Poly (o-Anisidine)/Triton X-100 Film onto Phosphotungstic Acid-Modified Carbon Paste Electrode
In this work, Phosphotungstic Acid modified Carbon Paste Electrode (PWA-CPE) is used as a substrate for electro-polymerization of o-Anisidine (OA). Also, Triton X-100 (TX-100) surfactant is used as an additive for electrochemical polymerization of OA onto the PWA-CPE, which is investigated as a novel matrix for dispersion of nickel species. The prepared electrodes are characterized by...
متن کاملKinetic Study of the Electrocatalytic Oxidation of Acetaldehyde at Ni/Al Layered Double Hydroxide Modified sol-gel derived carbon ceramic electrode
In this research, we reported a novel modified carbon ceramic electrode (CCE) using Ni/Al Layered double hydroxide as modifier was fabricated by sol-gel technique. The Ni/Al Layered double hydroxide modified sol gel derived carbon ceramic (Ni/Al LDH-SGD-CC) electrode was used for electrocatalytic oxidation of acetaldehyde. The oxidation of acetaldehyde happens at the potential where Ni (III) sp...
متن کاملPalladium nanoparticles supported on carbon black powder as an effective anodic catalyst for application in a direct glucose alkaline fuel cell
Palladium nanoparticles supported on carbon black powder (Vulcan XC-72) nanocomposite (Pd/C) are synthesized as the catalyst for the anodic oxidation of glucose for use in a direct glucose alkaline fuel cell (DGAFC). Characterization of the catalyst is carried out using physical and electrochemical methods. It is observed that Palladium nanoparticles are uniformly dispersed onto the carbon blac...
متن کامل