The influence of in situ synthesis parameters on the formation of ZnO nanoparticles and the UPF value of cotton fabric

Abstract

The aim of this research was to investigate different parameters of the in situ synthesis of ZnO nanoparticles on cotton in order to achieve a high ultraviolet protection factor (UPF). In the fi rst part of the research the influence of different reducing agents (Na2CO3, KOH, and NaOH) and their molar concentrations (0.1 M and 1 M) on the formation of ZnO nanoparticles and on the UPF values of cotton fabric were studied. The second part of the research was focused on the other parameters of in situ synthesis, such as the synthesis time ratio (time ratio between the treatment of the fabric in the precursor (ZnCl2) and treatment after the reducing agent was added) and drying period duration after the in situ synthesis. Using UV/Vis spectroscopy, high UPF values (UPF 50+) were measured for cotton fabrics where in situ synthesis was performed using NaOH and KOH, both at 1 M molar concentration. Inductively coupled plasma mass spectrometry (ICP-MS) revealed a higher content of zinc on the fabric when NaOH was used. Scanning electron microscopy (SEM) showed that use of this reducing agent resulted in cotton fabric completely covered with small, round shaped nanoparticles. From the second part of the research, it was found that longer treatment times after the reducing agent was added produced functionalised cotton fabric with higher UPF values. The drying period duration after in situ synthesis did not signifi cantly affect the UPF value of the fabric, but it did influence the morphology of the synthesised nanoparticles. With a longer drying time the nanoparticles were more rounded. The samples had poor wash fastness even after the fi rst wash, which was found through low UPF values.

Keywords

• KOH
• and NaOH) and their molar concentrations (0.1 M and 1 M) on the formation of ZnO nanoparticles and on the UPF values of cotton fabric were studied. The second part of the research was focused on the other parameters of in situ synthesis
• such as the synthesis time ratio (time ratio between the treatment of the fabric in the precursor (ZnCl2) and treatment after the reducing agent was added) and drying period duration after the in situ synthesis. Using UV/Vis spectroscopy
• high UPF values (UPF 50+) were measured for cotton fabrics where in situ synthesis was performed using NaOH and KOH
• both at 1 M molar concentration. Inductively coupled plasma mass spectrometry (ICP-MS) revealed a higher content of zinc on the fabric when NaOH was used. Scanning electron microscopy (SEM) showed that use of this reducing agent resulted in cotton fabric completely covered with small
• round shaped nanoparticles. From the second part of the research
• it was found that longer treatment times after the reducing agent was added produced functionalised cotton fabric with higher UPF values. The drying period duration after in situ synthesis did not signifi cantly affect the UPF value of the fabric
• but it did influence the morphology of the synthesised nanoparticles. With a longer drying time the nanoparticles were more rounded. The samples had poor wash fastness even after the fi rst wash
• in situ synthesis
• nanoparticles
• zinc oxide
• UV radiation
• cotton
• UV protection