Sol Gel Synthesis and Characterization of Carbides

Abstract

This chapter deals with the preparation, properties, electrochemical and electrical conductivity behaviour of carbides. Zirconium carbide (ZrC) was synthesized by a simple sol–gel method using zirconium n-propoxide, acetic acid, and saccharose as carbon source. The sol-gel processing of materials offers several potential advantages over conventional methods. The most important are improved properties regarding the specific microstructural features. The chapter presents the synthesis of ZrC powders by the sol-gel method. When heat-treated at 900ºC under flowing argon flow, gels transformed into intimately mixed amorphous raw powder. Further heat treatments above 1200, 1300, 1500ºC led to the formation of zirconium carbide with some dissolved oxygen in the lattice. The potential window and the electrochemistry of standard redox reactions have been investigated in 1 M KCl solution at a scan rate of 50 mV s-1using cyclic voltammetry in the potential region of -1 to 1.4 V. Electrochemical parameters of the carbide using organic electrolyte have been studied by cyclic voltammetry and electrochemical impedance spectroscopy. Electrical conductivity as a function of temperature in the range of 50-950ºC is also investigated.