Ag(I)-benzisothiazolinone complex: synthesis, characterization, H2 storage ability, nano transformation to different Ag nanostructures and Ag nanoflakes antimicrobial activity

Abstract

A new complex of silver monovalent ions with benzisothiazolinone was reported. This silver coordination polymer was characterized by FTIR, elemental analysis, 1H-NMR and 13C-{1H}-NMR). These measurements show that the bit anion in its silver complex behaves as μ-bridge linking two silver(I) ions as a bidentate ligand through the oxygen and nitrogen atoms. This coordinated polymer was showed non-melting ability, high decomposition and non-solubility in water in addition to all organic solvents except the hot DMSO solvent. Therefore, this polymeric complex had has a high porosity showing thereby that an overall H2 uptake of 5.5 mmol g−1 at 77 K and 10 bar. A new method for the synthesis of a mixture of three different morphological silver nano particles (AgNPs) is reported. The new method includes reduction of the newly prepared silver-benzisothiazolinone complex, [Ag(bit)]n (bit = benzisothiazolinone) with sodium borohydride without using stabilizing agent. The resulting silver nanoparticles Ag NPs were characterized by UV–vis spectra, powder XRD, zeta sizer, zeta potential and scanning electron microscopy (SEM). The results showed that [Ag(bit)]n complex gives three different nano-sized structures spherical, wires and flakes. In order to isolate the larger proportion of the nanostructures, experiments were conducted to control the formation of one form of silver as flakes nanosilver or silver nanowires. The prepared silver nanoparticles were screened for their antibacterial activity against K. pneumonia, P. Aeruginosa, S. aureus and E. coli. Inhibition zone diameter IZD results of 2, 4 and 6 mM Ag NPs was found to be in the range of 7.0–8.4 mm for the selected bacteria.