Efficient synthesis of carbon microtubes–gold nanoparticles composite: optical and micro-analytical study

This article reports a new synthesis method for the production of carbon microtubes–AuNPs composite (CMT–AuNPs) based on sucrose. The CMT showed the ability to functionalize gold nanoparticles. The UV–Vis spectroscopy was used to determine the surface plasmon resonance (SPR) of the nanoparticles and the absorbance of the CMT. The results showed two absorption bands centered at 287 nm and 527 nm, associated to carbon and gold structures, respectively. The Raman spectra revealed two bands, D and G, located at 1345 cm⁻¹ and 1570 cm⁻¹. Transmission electron microscope (TEM) and scanning electron microscope (SEM) were used to obtain structural properties of the CMT, the results show an approximate diameter size of 0.8–1.5 µm. Metallic gold NPs were observed between 15 and 30 nm adhered to the CMT surface. The NPs were analyzed with high-resolution imaging HRTEM and chemical analysis through energy dispersive X-ray spectroscopy EDS. This is the first report that uses sucrose as a precursor to obtain carbon microtubes with gold nanoparticles and opens up new ways to fabricate this material.