Photo-assisted oxidation of thiols to disulfides using cobalt “Nanorust” under visible light

Abstract

Heterogeneous “Nanorust” containing cobalt oxide has been developed for the visible light assisted oxidation of thiols to disulfides using molecular oxygen as an oxidant under alkaline free conditions and therefore more environmentally friendly. Pyrolysis of heterogenized tetrasulfonated cobalt(II) phthalocyanine (CoPcS) supported on mesoporous ceria (CeO₂) transforms it into a novel heterogeneous “Nanorust” containing CoO_x-C,N@CeO₂ which exhibited higher catalytic activity than the homogeneous CoPcS as well as the ceria immobilized CoPcS catalyst. Importantly, these catalysts could easily be recovered and recycled for several runs, which makes the process greener and cost-effective.