In situ green synthesis of Au/Ag nanostructures on a metal-organic framework surface for photocatalytic reduction of p-nitrophenol

Abstract

In this manuscript, we report the insitu growth of gold nanoparticles (GNPs) and silver nanoparticles (SNPs) over Ce/Tb-doped Y-benzene tricaroboxylate metal organic frameworks (MOF-76). The photocatalytic potential of these nanocomposites (NCs) was then assessed for the photocatalytic reduction of p-nitrophenol (p-NP) in aqueous medium. The NCs had large surface area to favorably showcase the efficient absorption of light energy. Correspondingly, it facilitated the electron transfer between the valance and conduction bands to promote the reductive removal of p-NP. Among the tested catalysts, GNPs@MOF-76 (Ce) (MOF-76(1a)) (dosage: 10 mu l of 5 mg.ml(-1)) recorded the maximum catalytic efficiency (96.3%) with an apparent rate constant (K-app': 0.33 min(-1)). Further, MOF-76 (1a) NCs exhibited good recyclability (e.g., a catalytic efficiency of 77.45% over 3 cycles). Moreover, the proposed NCs exhibited superior performance over commercial photocatalysts (e.g., p25 TiO2 nanopowder) towards p-NP reduction. As such, the results of this experimental study successfully demonstrated the superiority of the MOF immobilized nanoparticles (NPs) as an efficient platform for the removal of industrial grade pollutants.