Green synthesis of cobalt sulphide nanoparticles using synthesised cobalt (II) complex as a single route intermediate

Abstract

Nanotechnology is increasing at a very fast rate due to its many possible applications in the biomedical, industry, pharmaceuticals, commercial and their areas. In this paper, we have reported the biosynthesis of chalcogenide nanostructured pharmacologically active cobalt sulphide nanoparticles (CoS) using 3-ethylidene oxopropanamide thiosemicarbazone Co(II) chloride complex. The synthesised cobalt (II) complex of schilf base ligand was reacted with freshly prepared aqueous leaves extract of Nyctanthes arbour tistis (harsingar leaves) for synthesis of CoS nanoparticles. The biofabrication of CoS nonoparticles is a very simple, efficient, fast, eco-friendly and inexpensive method. In this method we use the aqueous environment for green synthesis of CoS nanoparticles. The use of aqueous medium plays a very important role in reducing reaction time, reducing minimum possibilities of side reactions and proper execution in conversion of very good quality of nanoparticles in a very less time. The synthesized compounds like schiff base, Co (II) complex and CoS nanoparticles were analyzed through various structure, morphological, electronic, vibrational and pharmacological characterizations. Powdered xray diffraction studies confirm the formation of well defined equispaced crystalline nanoparticles. Transmission election microscopy and FESEM microscopy exhibit rod like structures of CoS nanoparticles with an average particle size of 56 nm. Sharp electronic absorption band at 280 nm indicates the synthesis of good quality CoS nanoparticles. The FT-IR spectral studies confirmed the presence of Co –S stretching, N-H bending and C=N stretching vibrations in Cobalt complex of Schiff base ligand. The thermal analysis of cobalt complex was performed to investigate the thermal stability of complex. The cobalt complex was stable up to 300°c. The effective results of all pharmacological activities like in vitro antimicrobial, antioxidant and anti inflammatory activities explained the presence of strong electron withdrawing and election releasing functional groups are present in schiff base ligand and its Co (II) complex The biofabrication of CoS nanoparticles via aqueous extract of fresh leaves of Nyctanthes arbour tristis in proper stoichiometric ratio is a good method for synthesizing highly efficient bioactive agents which can be consider as a good drug candidate for various biological applications in future for mankind.