Covalent functionalization of single-walled carbon nanotubes using meso-tetra(4-aminophenyl) porphyrin and its zinc complex. Issue 10 (3rd October 2022)

• Record Type: Journal Article
• Authors: Prabhavathi, G.; Anakha, D. R; Yamuna, R.
• Is Part Of: Chemical engineering communications. Volume 209:Issue 10(2022)
• Page Start: 1293
• Page End: 1303
• Publication Date: 2022-10-03
• Subjects: Carbon nanotubes -- chromophores -- fluorescent quenching -- metalloporphyrin -- photo-luminescent -- solvatochromism; Chemical engineering -- Periodicals; 660.205
• DOI: 10.1080/00986445.2021.1957852
• Languages: English
• ISSNs: 0098-6445

Abstract

Abstract: Covalent linking of 5, 10, 15, 20 meso tetra(4-aminophenyl) porphyrin (TAP) and its zinc complex with single-walled carbon nanotubes (SWCNTs) (nanohybrids A and B, respectively) has been reported. Significant decrease in the intensity of D-band and higher frequency shift of G-band of SWCNT-TAP in Raman spectrum reveals the improved graphitic sp 2 hybridization of SWCNT as compared to SWCNT-ZnTAP. This is due to the functionalization of free base porphyrin (electron donating group) in the nanohybrid A . Shifting of carbonyl stretching frequency from 1700 cm −1 to 1680 cm −1 and further appearance of striking bands in the X-ray photoelectron spectroscopy (XPS) and FTIR spectra of nanohybrids A and B confirm the covalent linking of porphyrin chromophores with SWCNTs. XPS reveals that the extent of functionalization of nanohybrid A is more as compared to nanohybrid B . These nanohybrids demonstrate positive solvatochromism. Upon excitation at 450 nm, the nanohybrids A and B reveal ∼76% and 65% fluorescent quenching of emission bands at 686 and 632 nm, respectively. This is due to the energy or electron transfer from porphyrins to SWCNTs.