Thermally stable antibacterial wool fabrics surface-decorated by TiON and TiON/Cu thin films

Owing to the enormous production and various applications of wool, its modification has attracted increased attention. Nowadays, antibacterial properties are essentially of premier importance; hence, there has been an increasing interest in antibacterial wool fabrics in recent years, but the inadequate thermal stability of wool fabrics has limited their use for high-quality applications. Meanwhile, surface treatment of wool fabrics has become a solution to thermal and antibacterial shortcomings. In the present work, wool fabrics sputter-deposited by titanium oxynitride (TiON) and titanium oxynitride/copper (Cu) thin films are discussed. The microstructure of thin films was characterized by scanning electron and atomic force microscopies, contact angle and antibacterial analyses. The contact angle and thermal stability of wool fabrics decorated by titanium oxynitride were limitedly enhanced, while the antibacterial activity was significantly improved, as shown by c. 90% deleterious effect against Escherichia coli, but copper addition to titanium oxynitride resulted in c. 100% bacteria obliteration. Moreover, the increase of the copper content in titanium oxynitride/copper coating decreased water contact angle, while the thermal stability and antibacterial activity were enhanced. It was found that it is possible to regulate the hydrophobicity, thermal stability and antibacterial activities of wool fabrics sputter-coated with titanium oxynitride/copper, paving the way for expanding wool fabric as an eco-friendly substance.