COVALENT LINKING OF Ni (II) COMPLEX OF MESO TETRA(4-AMINOPHENYL) PORPHYRIN WITH SINGLEWALLED CARBON NANOTUBE AND ITS PHOTO-PHYSICAL PROPERTIES

Abstract

5, 10, 15, 20 meso tetra(4-aminophenyl) porphyrinato nickel (II) complex (Ni-TAP) was connected covalently with a single-walled carbon nanotube (SWCNT). The Infrared (IR) spectrum of SWCNT-NiTAP nanohybrid conveys the shifting of C=O stretching frequency from 1714 cm-1 to 1695 cm-1 which substantiates the covalent bond connection of porphyrin with SWCNT. In Raman spectroscopy, there is a decrease in the ID/IG ratio after the covalent linkage of SWCNT with Ni-TAP compared to SWCNT-COOH, which specifies enriched electronic properties of SWCNTNiTAP. This is perhaps due to the method of acylation. The morphology study of SWCNT-NiTAP retains the tubelike structure even after the covalent functionalization. The presence of significant peaks in the C 1s and N 1s XP spectra of SWCNT-NiTAP indicate the covalent bond connection of porphyrin chromophores on SWCNTs. Fluorescence spectra of SWCNT-NiTAP show that effective fluorescent quenching is due to energy or electron transfer from Ni-TAP to SWCNTs. Moreover, SWCNT-NiTAP reveals hypsochromic shift compared to Ni-TAP, which specifies the covalent linkage of SWCNT with Ni-TAP.