Silver and palladium nanoparticle embedded poly(n-isopropylacrylamide-co-2-acrylamido-2-methylpropane sulfonic acid) hybrid microgel catalyst with pH and temperature dependent catalytic activity

Here in, we demonstrate facile fabrication of silver and palladium nanoparticles in dual responsive poly(N-isopropylacrylamide-co-2-Acrylamido-2-methylpropane sulfonic acid) microgel with temperature- and pH-dependent catalytic potential. Palladium-based catalyst showed better catalytic efficiency as compared to silver-based catalyst for degradation of Rhodamine-B and P-Nitrophenol in aqueous medium under the same set of reaction conditions. The responsive nature of the microgel was found to be useful to tune the catalytic activity of the as-prepared catalysts, and reduction rate was enhanced with the pH and temperature elevation of the reaction medium; however, the increasing trend was slowed in the volume phase transition region of the microgel. Under a specific set of reaction conditions, the reduction of Rhodamine-B was as fast as 0.968 and 0.571 min(-1) when catalyzed with palladium and silver based catalysts, respectively. The hydrodynamic radius of the particles of microgel support was found to be in the range of 65180 nm when pH and temperature of the medium were varied in the range of 2-12 and 25-45, respectively. The estimated diameter of silver and palladium nanoparticles fabricated in the microgel support under the same set of reaction conditions was 9-15 and 7-11 nm, respectively.