Facile construction of calix[4]pyrrole-templated gold nanoparticles: computational insights and application for efficient reduction of 4-nitrophenol

Herein, we report a simple one-pot synthesis of water-dispersible gold nanoparticles (AuNPs) by using meso-tetra(methyl) meso-tetra hydrazide-functionalized calix[4]pyrrole (ECPTH) as both reducing and stabilizing template. The characterization of ECPTH-AuNPs has been carried out by UV-Vis spectroscopy, transmission electron microscope, X-ray diffraction (XRD), dynamic light scattering (DLS), and zeta potential techniques. The spherical shaped nanoparticles are highly stable with an average size of 8 ± 2 nm. The mechanistic insights rendered by the computational study have suggested that ECPTH can successfully cap the Au via utilizing the hydrazide arms. The nanoparticles functioned as an effective heterogeneous catalyst for the 4-nitrophenol reduction and ECPTH as capping ligand enhances the catalytic activity via a synergistic effect. This work contributes a new catalytic pathway for the degradation of hazardous and toxic pollutants using highly efficient and cost-effective supramolecular-functionalized nanocatalyst.