Morphological, structural and antibacterial behavior of eco-friendly of ZnO/TiO₂ nanocomposite synthesized via Hibiscus rosa-sinensis extract

An eco-friendly preparation technique was used to synthesize zinc oxide (ZnO) from Hibiscus rosa-sinensis extract. In addition, titanium dioxide (TiO2) was combined with ZnO in a nanocomposite. The structural investigation was done by x-ray diffraction (XRD) and the hexagonal symmetry of ZnO was detected. The calculated crystallite size of ZnO increased from 31.3 to 34.4 nm. Furthermore, functional groups of organic residues were detected by chemical analysis of Fourier transform infrared spectroscopy (FTIR). The rod grains of ZnO and TiO2 were detected by scanning electron microscope (SEM). Further, ZnO grains increased in length from 0.87 to 4.5 μm. Besides, the width increased from 0.27 to 2 μm (from ZnO to ZnO/TiO2 respectively). Furthermore, TiO2 grains decreased in length from 536 to 337 nm, while the width decreased from 136 to 122 nm. A transmission electron microscope (TEM) was used to investigate the particles of ZnO/TiO2 composite. ZnO particles were detected as ellipsoidal with length and width around 123 and 91 respectively. Besides the sphere particles of TiO2 with a diameter around 25 nm. The eco-friendly composites without harmful chemicals could be suggested for biological applications. The inhibition zone values of E. coli and S. aureus microorganisms was 61.4 ± 3.6 and 39.6 ± 4.4 and has been increased by by doping by TiO2 to 82.3 ± 6.7 and 54.3 ± 2.8