An Efficient Method for Fabrication of Carboxylated Short Multi-walled Carbon Nanotubes Decorated with Magnetic Iron Oxide Nanoparticles

A low cast, full efficient and short term procedure for magnetization of carboxylated short multi-walled carbon nanotubes c- SMWCNTs was innovated in this work. Carboxylic acid groups were functionalized on SMWCNTs by refluxing in concentrated mixture of HNO3 and H2SO4 (1:3, v/v) solution. The remaining acid of the solution was neutralized by NaOH base until pH value reached 11 and then Fe3O4 nanoparticles were attached on the outer surfaces of c-SMWCNTs by co-precipitation. Different analyses were used to confirm the decoration of c-SMWCNTs with Fe3O4 nanoparticles. Fourier transform infrared (FTIR) spectroscopy, which is used to evaluate chemical bonds, confirmed that the carboxylic acid groups generated on the SMWNTs while scanning electron microscopy (SEM). Investigation of FTIR peaks of O–H and C=O bonds and shift of X-ray diffraction (XRD) peaks demonstrated that the Fe3O4 nanoparticles were attached on the c-SMWCNTs. Energy-dispersive X-ray (EDX) analytical technique was also used to investigate identity and quantity of the elements.