SYNTHESIZE AND CHARACTERIZATION OF SILVER NANOPARTICLES USING MANGROVE HUMIC ACIDS AND THEIR ROLE AS CATALYST IN THE DEGRADATION OF ORGANIC DYESJENNEES MATHEW, ANU GOPINATH, JITHA G., ROSILY A.V., PASICHNA O.O. AND GORBATIUK L.O.Abstract The present study focuses on the isolation and characterisation of humic acid isolated from tropical mangrove sediments from the south west coast of India and their use in the formation of selfassembled humic âsilver supramolecules. The silver nanoparticles (AgNPs) with higher stability were prepared in a completely green and cost effective manner using aqueous extract of humic acids synthesised using standard procedure IHSS 2010. The humic acids were extracted from the mangrove sediments collected from Mangalavanam bird sanctuary (Kochi) in April 2018. Silver nanoparticles were synthesised by the reduction of silver nitrate in the presence of humic acids (HA) which acted as capping agents. The characterization studies were carried out using by FT-IR, UV-Visible spectroscopy and HR-TEM. The high crystallinity of the biogenic AgNPs was confirmed from clear lattice fringes in the HR-TEM image, bright circular spots in the SAED pattern and tuning of dipole and quadrapole oscillation (silver nanoparticles size of 5 nm). The study also highlights the spectroscopic investigation on the catalytic efficacy of the biosynthesized AgNPs in the reduction reactions of hazardous organic dyes like Congo red and Methylene blue using sodium borohydride. |