Functionalized Agarose Hydrogel with in Situ Ag Nanoparticles as Highly Recyclable Heterogeneous Catalyst for Aromatic Organic Pollutants

Abstract

Abstract In the present research work, a highly recyclable catalyst of Ag-based agarose (HRC-Ag/Agar) hydrogel was successfully fabricated through a simple and efficient in situ reduction method without the aid of additional surface active agent. The interaction between the rich -OH groups in agarose and the Ag nanoparticles can effectively control the growth and dispersion of Ag nanoparticles in the HRC-Ag/Agar hydrogel. Moreover, HRC-Ag/Agar hydrogel without freeze drying and calcination can be directly used as a highly active catalysts in reducing aromatic organic pollutants (4-NP, RhB and MB) by KBH4. HRC-Ag/Agar hydrogel also show great advantages in separation and reusability of catalysts due to Ag attach to the agarose toughly via the interaction between Ag NPs and –OH groups and the chemical reactant has no significant damage to the Ag NPs, which can maintain high catalytic efficiency with no significant loss during ten cycles testing. The advantages of simple synthetic procedure, no secondary pollution, strong stability and the product easily separated make the HRC-Ag/Agar hydrogel have great potential prospect for environmental applications. The successful synthesis of the material was confirmed through SEM, EDS, XRD, Raman and FTIR techniques.