Cellulose/metal sulfide (CL@HgS, CL@FeS and CL@PbS) nanocomposites: synthesis, characterization, thermal study and antibacterial activity

In this paper, three cellulose/metal sulfide (CL@HgS, CL@FeS and CL@PbS) nanocomposites were synthesized in situ and characterized by FT-IR, XRD, EDS-SEM, DSC and TGA. All results showed the permanent embedding of single phase of HgS, FeS and PbS nanoparticles on the cellulose polymer. The presence of HgS, FeS and PbS nanoparticles on the surface of cellulose can be clearly seen in the SEM images. This is also confirmed by the results of EDS elemental analysis and XRD patterns. The intensity of peaks in as-prepared nanocomposite is lower than pure chitosan, predicted that the low crystallinity of prepared compounds. Thermogravimetric results (TGA) confirmed the better thermal stability of CL@FeS and CL@PbS than CL@HgS. The residue weight at the temperature of 800 °C is the highest for CL@FeS nanocomposite and is about 66%. DSC thermogram of CL@FeS is completely different from the CL@PbS than CL@HgS, because it shows a sharp and strong peak related to the oxidation of Fe(II) to Fe(III) at a temperature of 276.1 °C. Finally, antibacterial activities of the as-prepared nanocomposites showed the more effective of CL@HgS nanocomposites against S. aureus and E. coli than CL@FeS and CL@PbS.