1-Substituted Tetrazole-5-thiol-Capped Noble Metal Nanoparticles

Stable and nearly monodispersed silver, palladium, and platinum nanoparticles with an average size of 2–4 nm were synthesized by the reduction of metal precursors (CF 3 COOAg, [NMeAlk 3 ] 2 MCl 4, where M = Pd, Pt) in a biphasic toluene–water system in the presence of easily available 1-R-tetrazole-5-thiols (R = ethyl, tert -butyl, 1-adamantyl, and phenyl) characterized by low carbon content and unique thermal behavior. The obtained noble metal nanoparticles capped with tetrazole-5-thiols were characterized by TEM, TGA, UV–vis, and FTIR spectroscopy. Based on quantum-chemical calculations, preferred coordination mode of the ligands under their binding with surfaces of nanoparticles, namely N(4), S-bridging was proposed. The synthesized silver nanoparticles capped with 1-phenyltetrazole-5-thiol were found to have antifungal and antimicrobial activity against various bacterial strains.