"Nanocomposites and nanomaterials"

5-Alkyl-1,2,4-triazole-3-thiones as stabilizers in the synthesis of silver nanoparticles
Fizer M.M.1, Hryhorka H.V.1, Slivka M.V.1, Fizer O.I.1, Mariychuk R.T.2
1 Organic Chemistry Department, Educational and Scientific Institute of Chemistry and Ecology, Uzhhorod National University, Pidhirna, 46, Uzhhorod-88000, Ukraine. 
E-mail: mmfizer@gmail.com
2 Department of Ecology, Faculty of Humanity and Natural Sciences, University of Presov in Presov, 17th November, 1, Presov-08116, Slovak Republic.

Several novel 5-alkyl-4-methyl-1,2,4-triazole-3-thiones (alkyl can be pentyl, heptyl, pentadecyl, and heptadecyl) were synthesized from hydrazides of corresponding acids. Obtained triazoles exist in the form of thiolate anions in an alkaline medium, they are characterized by structural features of surfactants. The alkyl chain acts as a “hydrophobic tail,” while the more polar negatively charged fragment of 1,2,4-triazole-3-thiolate acts as a “hydrophilic head.”
It is known from the literature that structurally similar 4-amino-5-hexyl- 1,2,4-triazole-3-thione can be used as a flotation collector in the treatment of malachite [1]. The authors note that the surface activity is due to the interaction of sulfur and nitrogen atoms with the surface of malachite. Moreover, it was shown a strong binding of thiolate-containing stabilizers to silver nanoparticles [2].
Considering all the above, it was decided to investigate the possibility of using alkaline solutions of 5-alkyl-4-methyl-1,2,4-triazole-3-thiones as stabilizers in the chemical synthesis of silver nanoparticles. A series of solutions of silver nanoparticles of different concentrations were synthesized. It was found that triazoles with longer chains (5-pentadecyl, 5-heptadecyl) have a more significant stabilizing effect than triazoles with pentyl or heptyl groups. 

1.	Liu G., Huang Y., Qu X., Xiao J., Yang X., Xu Z. Understanding the hydrophobic mechanism of 3-hexyl-4-amino-1, 2,4-triazole-5-thione to malachite by ToF-SIMS, XPS, FTIR, contact angle, zeta potential and micro-flotation // Colloid Surf A-Physicochem Eng Asp.-2016.-503.-P. 34-42.
2.	Marchioni M., Battocchio C., Joly Y., Gateau C., Nappini S., Pis I., Delangle P., Michaud-Soret I., Deniaud A., Veronesi G. Thiolate-capped silver nanoparticles: discerning direct grafting from sulfidation at the metal–ligand interface by interrogating the sulfur atom // J Phys Chem C.-2020.-124.-P. 13467–13478.