Infrared absorption spectra analysis of amine-modified carbon-based nanoparticles synthesised using submerged arc discharge method with gas injection

Abstract

Surface modification of carbon-based nanoparticles has become essential and is challenging for bio-applications. The submerged arc discharge method is a promising technique because liquid can be used as the medium for both synthesis and surface modification at once. Submerged arc discharge using gas injection is rarely applied; therefore, the surface characteristics of the nanoparticle product have not yet been reported in detail. In this study, we investigated those surface characteristics using Fourier transform infrared (FTIR) spectroscopy to analyse the functional groups attached to the carbon nanoparticle produced by submerged arc discharge in ethylenediamine medium under different gas injections of N2 and Ar. The FTIR analysis indicated successful amine-surface modification of nanoparticles produced in arc discharge in the ethanol-ethylenediamine medium. This conclusion was reached from the observation of several absorption peaks at wavenumbers of 1020 cm-1, 870 cm−1, and 700 cm−1 as C-N vibrations, NH2 wagging and twisting, and NH2 bending, respectively. The effect of variations of gas injections influences the characteristics of FTIR spectra. Altogether, the representative peaks of amine groups have different performance signals due to variations of gas injections.