Modification of the properties of carbon nanocoils by different treatments in liquid phase

Abstract

Carbon nanocoils (CNCs) were synthesized using resorcinol–formaldehyde gel as carbon precursor and a mixture of cobalt and nickel salts as the graphitization catalysts. The last step of the synthesis process involves the elimination of the metals using an oxidative treatment, commonly HNO 3 treatment. However, during this treatment not only the metals are eliminated, but also the amorphous and graphitic carbon. On the other hand, this treatment can create surface oxygen groups, modifying the surface chemistry of CNCs. The aim of this work is to study the effect of different oxidative treatments on the final properties of carbon nanocoils in order to obtain materials with high graphitic character. The effect of liquid phase oxidation treatments on the texture, surface chemistry and structure of carbon nanocoils was studied by means of different analytical techniques as N 2-physisorption, X-ray diffraction (XRD), temperature programmed oxidation (TPO) and temperature programmed desorption (TPD). During these treatments, surface oxygen groups were created and their number was function of the concentration of the oxidizing agent used and the treatment time.