Preparation of silver nanoparticles using atmospheric discharge plasma for catalytic reduction of p-nitrophenol: the influence of pressure in the reactor

Abstract

PurposeThis paper aims to synthesize silver nanoparticles using atmospheric discharge plasma in contact with liquid at different pressure in reactor and to assess their catalytical properties for reducing 4-nanoparticles (NP).Design/methodology/approachThe Ag colloidal NPs was rapidly synthesized as a result of non-equilibrium low-temperature plasma formation between an electrode and the surface of AgNO3 solution for 5 min at different pressure in reactor. Synthesized Ag NPs were characterized with common analytical techniques. Ultraviolet–visible (UV) spectroscopy, dynamic light scattering, scanning microcopy analysis were used to study the formation and characteristics of silver nanoparticles.FindingsThe formation of silver colloidal solutions under plasma discharge at different pressure in reactor is characterized by the presence of surface resonance peak in the spectra. Scanning electron microscope (SEM) images confirmed the formation of spherical particles having a size distribution in the range of 15-26 nm. The AgNPs solution showed excellent rapid catalytic activity for the complete degradation of toxic 4-nitrophenol (4-NPh) into non-toxic 4-aminophenol (4-APh) within 18 min.Research limitations/implicationsFurther studies are necessary for confirmation of the practical application, especially of deposition Ag NPs on TiO2.Practical implicationsThe method provides a simple and practical solution to improving the synthesis of colloidal solutions of Ag NPs for degradation of organic pollutants (4-NPh) in water and wasters water.Originality/valueAtmospheric discharge plasma in contact with liquid at different pressure can be used as an effective technique for synthesis of nanomaterials with catalytic properties.