Fabrication of graphene/ chitosan films by two step elecrodeposition

Abstract

Electrochemical deposition is a versatile surface modification technology for the realization of advanced coatings for electrochemical sensor applications.<br><br>This paper proposed a simple electrodeposition approach to synthesis graphene- chitosan composite onto glassy carbon electrode. The whole procedure was<br><br>simple and it last only several minutes. Moreover, combining the advantages of graphene( large surface- to- volume ratio and high conductivity) and<br><br>chitosan( good mechanical strength and adsorption), the composite film could be highly efficient to use in surface electrode [1-3]. Although the feasibility of<br><br>chitosan electrodeposition was already demonstrated, here we have showed that chitosan acts as a protective layer enhancing the stability of graphene sensor.<br><br>Graphene can be synthesized by chemically reduction of graphene oxide. On the other hand, the use of reducing agents also have several disadvantages.<br><br>These materials have a potential health hazard and high expense. Thus graphene electrodeposition approach for construction of graphene based was<br><br>environmental friendly. Also, compared with conventional methods producibility of film preparation has significantly improved [4]. Graphene oxide structure<br><br>were investigated by Fourier trasform infra red spectroscopy (FT-IR) and scanning electron microscopy (SEM). The electrode was characterized using<br><br>differential pulse voltammetry (DPV) and cyclic voltammetry (CV). Here we used cyclic voltammetry for graphene deposition and chorno potentiometry for<br><br>chitosan deposition. The effect of influential parameters such as mass of graphene oxide, pH, cycle numbers, the sonication time and scan rate in firs step<br><br>deposition and chitosan solution concentration, pH, time and current of deposition in second step were optimized to obtain the maximal sensitivity.