Covalent functionalization and characterization of multi-walled carbon nanotubes using 5, 10, 15, 20-tetra(4-aminophenyl)porphyrinatonickel(II)

• Published in: Fullerenes, nanotubes, and carbon nanostructures nanotubes, and carbon nanostructures, 2018-11, Vol.26 (11), p.739-745
• Main Authors: Jafer, Alifia C., Veetil, Vyshnavi T., Prabhavathi, G., Yamuna, R.
• Format: Article
• Language: English
• Subjects: fluorescence quenching; hyperchromic shift; hypsochromic shift; MWCNT-NiTAP; solvatochromism
• ISSN: 1536-383X; 1536-4046
• DOI: 10.1080/1536383X.2018.1492558

5,10,15,20-tetra(4-aminophenyl)porphyrinatonickel(II) was covalently connected to multi-walled carbon nanotube (MWCNT) through an amide linkage and characterized by using many spectroscopic techniques. In FT-IR, the carbonyl peak (C = O) of MWCNT-NiTAP is shifted to higher frequency as compared to the reported MWCNT-TAP due to Ni ion substitution. Notable changes in the FT-IR and XP spectra confirms the covalent functionalization of Ni-TAP with MWCNTs. Raman spectra indicate that the ID/IG ratio is less for MWCNT-NiTAP as compared to MWCNT, MWCNT-COOH, MWCNT-ZnTAP and MWCNT-CuTAP which is due to improved electronic properties of MWCNT-NiTAP. TGA plots of MWCNT-NiTAP reveals that ∼30% weight loss in the temperature range of 150-800 °C. Considerable shift in the absorption and emission spectra of the nano hybrid clearly indicate different electronic interaction between porphyrin and MWCNT due to nickel ion substitution. PL spectra of MWCNT-NiTAP exhibited fluorescence quenching of Ni-TAP Soret band by MWCNTs. This quenching is owing to the energy or electron transfer between Ni-TAP and MWCNTs.