Hybrid hexagonal nanorods of metal nitride clusterfullerene and porphyrin using a supramolecular approach

Abstract

Hexagonal nanorods of metal nitride clusterfullerene Sc₃N@C₈₀ (I_h) encapsulated in zinc meso-tetra(4-pyridyl) porphyrin (ZnTPyP) (Sc₃N@C₈₀-ZnTPyP nanorods) are prepared for the first time using a supramolecular approach. By introducing water as the solvent of cetyltrimethylammonium bromide (CTAB) surfactant, the effects of the solvent and the ratio of the reactants have been studied so as to control the length and size distribution of the Sc₃N@C₈₀-ZnTPyP nanorods. The encapsulation nature and hybrid structures of Sc₃N@C₈₀-ZnTPyP nanorods are confirmed by TEM, EDX, TGA and Raman spectroscopies. XRD study on the internal structure of Sc₃N@C₈₀-ZnTPyP nanorods suggests that ZnTPyP molecules tend to self-assemble in the axial direction. The UV-vis electronic absorption spectrum of Sc₃N@C₈₀-ZnTPyP nanorods shows broader and stronger absorptions in the visible region than those of the components Sc₃N@C₈₀ and ZnTPyP. The comparison of the UV-vis electronic absorption spectra of Sc₃N@C₈₀-ZnTPyP and C₆₀-ZnTPyP nanorods reveals the influence of the electronic structures of fullerenes on the aggregative interactions between fullerene and ZnTPyP. The fluorescence emission intensity of Sc₃N@C₈₀-ZnTPyP nanorods exhibits a strong quenching (∼88%) compared to the pure ZnTPyP nanotubes, suggesting that photo-induced electron transfer from the excited ZnTPyP to Sc₃N@C₈₀ might occur. An electrochemical study of Sc₃N@C₈₀-ZnTPyP nanorods in comparison with those of ZnTPyP and Sc₃N@C₈₀ corroborate the hybrid nature of Sc₃N@C₈₀-ZnTPyP nanorods and reveal the interactions between Sc₃N@C₈₀ and ZnTPyP molecules.