Photocatalytic desulfurization of dibenzothiophene using asymmetrical zinc (II) phthalocyanines conjugated to silver-magnetic nanoparticles

Asymmetrical Zn(II) phthalocyanines: mono (4-carboxy phenoxy) tris (phenylazo phenoxy) (1), mono (4-amino phenoxy) tris (phenylazo phenoxy) (2), mono (4-propanoic acid phenoxy) tris (phenylazo phenoxy) (3) zinc(II) phthalocyanines are synthesized and covalently linked to mercaptohexanol (mph) or mercaptopropionic acid (mpa) functionalized dimerized silver-magnetic nanoparticles (Ag-M). Complexes 1 and 3 are covalently linked to nanomaterials via ester bond whereas complex 2 is covalently linked to nanoparticles (NPs) via amide bond. The conjugates of complexes 1-3 with NPs gave higher singlet oxygen quantum than the Pcs alone. Electrospun fibers were fabricated from polystyrene (PS) solutions containing complexes 1 to 3 and their conjugates. The functionalized PS fibers were used for the phototransformation of dibenzothiophene. The increase in photocatalytic properties of phthalocyanines was observed in the presence of Ag-M with 3 alone and its conjugate with mph capped silver-magnetic nanoparticles showing the larger catalytic activity towards the transformation of dibenzothiophene.