Impact of γ-irradiation on the structural and electrical characteristics of functionalized multiwalled carbon nanotubes

Abstract

In the present study, modifications induced in the functionalized multiwalled carbon nanotubes (FMWCNTs) by gamma (γ) irradiation are explored. Functionalization of pristine MWCNTs is performed by acid treatment and their films are deposited via doctor-blading technique on the glass substrate. As-deposited films are exposed with the γ–ray irradiation at various doses of 60 kGy, 120 kGy, 180 kGy, and 240 kGy to examine the alteration in structural, morphological and electrical characteristics. XRD analysis of pre and post gamma irradiated FMWCNTs films revealed that there is no phase variation in the post irradiated samples. The crystalline nature of films is enhanced after gamma exposure up to 180 kGy and decreased at a dose of 240 kGy. Raman spectral analysis identifies the structural ordering/disordering developed in the nanotubes after gamma irradiation of different doses. XPS analysis is exploited to expose the chemical composition in pre and post irradiated FMWCNTs. FTIR spectra exhibited the presence of different functional groups like O–H, O–CO and CO, etc. in pristine and gamma irradiated nanotubes. The significant variation in the electrical properties of gamma irradiated nanotubes is also noticed. The fluctuation in the properties of irradiated nanotubes may be due to defects generation, annihilation, and ionization process.