This work reports the fabrication of Au nanoparticles (NPs) by laser ablation of a gold metal plate immersed in water in the absence of stabilizing agents and their application in the catalytic reduction of 4-nitrophenol (4-NP) to 4-aminophenol (4-AP) using sodium borohydride (NaBH4) in aqueous media at ambient temperature. UV–Vis, EDS (energy-dispersive X-ray spec- troscopy), FESEM (feld emission scanning electron microscopy), transmission electron microscopy and inductively coupled plasma-optical emission spectrometry analyses have been applied for the characterization of Au NPs which afrmed that they were successfully synthesized and their size ranged from 5–30 nm. The reduction rate for 4-NP with Au NPs using NaBH4 was measured via UV–Vis spectroscopy from 250 to 550 nm. The clean and eco-friendly protocol presented here neither produces hazardous wastes nor uses any toxic organic solvents, hazardous reductants and expensive surfactant template or capping agents; Au NPs display high catalytic activity as the reaction was completed within 20 min with 100% conversion.
