Antimicrobial particles based on Cu2ZnSnS4 monograins

In this research, Cu2ZnSnS4 (CZTS) particles were successfully fabricated via the molten salt approach from the copper, zinc and tin sulphides as raw precursors. SEM analysis revealed that CZTS particles are tetragonal-shaped with sharp edges, smooth flat plane morphology, and crystal size varying from 10.8 to 28.7 & mu;m. The phase and crystalline structure of synthesized powders were investigated using XRD analysis, which confirms the presence of a tetragonal crystal structure kesterite phase. The chemical composition of CZTS particles was evaluated by EDX spectroscopy, which identified the nearly stoichiometric composition with an averaged formula of Cu1.88Zn1.04SnS3.97. The TG/DTA-MS and ICP-OES analysis showed the possible decomposition pathways and predicted their degradation rate in aqueous solutions. The CZTS particles possessed highly effective concentration and time-dependent antimicrobial properties against medically relevant bacteria and yeast strains. The CZTS particles (1 g L-1) exhibited over 95.7 & PLUSMN; 1.9% killing efficiency towards M. luteus. In contrast, higher dosages (3.5 and 5 g L-1) led to its complete inactivation and reduced the P. aeruginosa cell viability to 43.2 & PLUSMN; 3.2% and 4.1 & PLUSMN; 1.1%, respectively. Moreover, the CZTS particles (0.5 g L-1) are responsible for causing 54.8 & PLUSMN; 1.8% of C. krusei and 89.7 & PLUSMN; 2.1% of C. parapsilosis yeasts death within the 24 h of exposure, which expanded to almost 100% when yeasts were treated with two times higher CZTS concentration (1.0 g L-1). The mechanism of action has been proposed and evidenced by monitoring the 2 & PRIME;,7 & PRIME;-dichlorofluorescein (DCF) fluorescence, which revealed that the overproduction of reactive oxygen species (ROS) is responsible for microorganism death.

Automated summary

In this study, CZTS particles were successfully synthesized using the molten salt approach from raw precursors. SEM analysis revealed the tetragonal shape and crystal size of the CZTS particles. XRD analysis confirmed the presence of a tetragonal crystal structure kesterite phase. The CZTS particles exhibited antimicrobial properties against medically relevant bacteria and yeast strains, with high killing efficiency and the overproduction of reactive oxygen species playing a role in microorganism death.