We characterize ZnO-nanorod fibres doped with different concentrations of TiO2 powder which is introduced on the final stage of synthesis of ZnO nanorods, using a low-temperature hydrothermal method. Their surface morphology, size of particles, behaviour of crystallites and optical properties are investigated using techniques of scanning electron microscopy (SEM), energy-dispersive X-ray
spectroscopy (EDS), X-ray diffraction (XRD) and an optical spectrometer. A presence of ZnO nanorods and a globular structure of TiO2 are confirmed by the SEM analysis. The EDS spectra and chemical-element mapping reveals a presence of Ti incorporated into a globular surface, along with Zn. The XRD analysis testifies that ZnO doped with TiO2 has a primary crystallite phase of ZnO. ZnO doped with 10 and 15 mM of
TiO2 shows a stronger and more expressed peak corresponding to (002) and (011) planes, which implies improved crystallinity of ZnO–TiO2 system. Optical properties
of ZnO–TiO2 are studied by measuring the intensity of halogen-source light transmitted through the fibres. The ZnO & 15 mM TiO2 fibre sample shows the lowest intensity of the transmitted light due to higher refractive index of a cladding layer coated under condition of high TiO2 concentration. The increased light leakage in such a fibre can improve sensitivity of a relevant sensor, especially a gas one