Effect of microwave power on bactericidal and UV protection properties of the ZnO nanorods grown cotton fabrics

In this present work, vertically oriented ZnO nanorods (NRs) were grown at various microwave radiations (300 W, 360 W, 450 W, 540 W) through a fast and low cost microwave hydrothermal method. The effect of microwave power on the bactericidal, UV protection and thermal properties of cotton fabrics has been studied. The morphology of the ZnO NRs was investigated in detail using scanning electron microscopy (SEM). The topog-raphy of the cotton fabrics was observed by using atomic force microscopy (AFM). ZnO NRs-grown cotton fabrics were characterized via energy-dispersive X-ray spectroscopy (EDS) analysis, X-ray diffraction (XRD) techniques and thermogravimetric analysis (TGA). The results showed that the microwave power influenced the shape and size of the synthesized ZnO NRs. It was found that the length and diameter of the ZnO NRs increased with increasing microwave power. The ZnO NRs-grown at 450 W and 540 W exhibited 100 % ability to kill and prevent growth against both types of Gram-negative (E. coli) and Gram-positive (S. aureus) bacteria. The coated cotton fabrics also showed excellent UV protection performance against harmful UV radiations. The maximum UV blocking was observed in the case of NRs-grown fabric at 540 W, where UV transmittance decreased from 26.6 % of untreated fabric to 4.0 % of coated fabric. Moreover, the presence of uniform layer of ZnO NRs on the fiber surface contributed to the enhancement of thermal stability of the cotton fabrics. The current methodology is faster, simple and cost effective compared with conventional method for the synthesis of ZnO NRs.