Hybrid hydrogels containing one-step biosynthesized silver nanoparticles: Preparation, characterization and catalytic application

Publication date: 25 November 2019Source: Journal of Industrial and Engineering Chemistry, Volume 79Author(s): Rafael F.N. Quadrado, Gustavo Gohlke, Robson S. Oliboni, Alessandra Smaniotto, André R. FajardoAbstractSilver nanoparticles (AgNPs) were synthesized using an innovative strategy that makes use of tangerine peels extract, which acts as a reducing and stabilizing agent. This eco-friendly synthetic route allowed obtaining spherical nanoparticles with narrow size distribution (19.2 ± 6.7 nm) within a short reaction time (40 min). Later, the AgNPs suspension was entrapped in a poly(vinyl alcohol) (PVA) matrix forming a hybrid hydrogel (PVA-gel/AgNPs), which was characterized by different techniques. Its catalytic activity was explored in the reduction of nitrobenzene to aniline in aqueous media. The reaction catalyzed by PVA-gel/AgNPs exhibited kinetics (kapp ≈ 2.07 × 10−3 min−1) and energy of activation (Ea ≈ 50.36 kJ mol−1) comparable to or lower than similar reactions catalyzed by other metals. Moreover, a better catalytic performance was noticed to the hybrid hydrogel as compared to “free” AgNPs, highlighting their entrapment within the hydrogel. The anchoring of the AgNPs in the hydrogel network, prevents their aggregation and leaching. The hybrid hydrogel is recovered quickly from the reaction medium, and it can be successfully reused for six consecutive runs without significant loss o...
Source: Journal of Industrial and Engineering Chemistry - Category: Chemistry Source Type: research