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In the framework of this study, pure and Li-doped TiO 2 (0.5, 1.5, 2.5 at.%) thin film samples were synthesised via sol–gel spin coating method. The structural, morphological and optical properties were examined by using X-ray diffraction, scanning electron microscopy (SEM) and UV–Vis spectroscopy respectively. XRD pattern reveals the polycrystalline nature of Li-doped TiO 2 thin films with anatase crystal phase. The average crystallite sizes were found to be in the range of 19–23 nm. The energy-dispersive X-ray spectroscopy (EDS) demonstrates the oxidation states of Ti, O and Li in the deposited thin films. The optical band gap of TiO 2 thin films was varied from 3.15 to 3.26 eV on increasing Li doping. For the study of light emission properties of Li-doped TiO 2 thin films, the PL spectra were recorded in the wavelength range of 350–700 nm. The doping of Li on TiO 2 films show improved charge transport properties which can be used in optoelectronics and energy storage devices. [ABSTRACT FROM AUTHOR]

In this study, n-type CdyZn1−yO (y = 0, 0.5, 1, 1.5 at%) thin films were deposited on p-Si and soda lime glass substrates using sol–gel spin coating technique. From the X-ray diffraction patterns, it was observed that all thin films had wurtzite structure with (002) orientation. Scanning electron micrograph results revealed that the morphology varied with higher Cd doping in ZnO. The bandgap was decreased from 3.29 eV (undoped ZnO) to 3.26 eV (y = 1.5 at%) as Cd content increased. The electronic parameters of the CdyZn1−yO (y = 1 at%) thin film heterojunction such as ideality factor (η) and barrier height (ΦB) were obtained using the thermionic emission theory as 2.53 and 0.70 eV, respectively. CdyZn1−yO (y = 1 at%) showed responsivity 0.01 A/W on 3.2 mW/cm2 exposure of UV light (365 nm) at 4 V bias voltage. The heterojunction so formed seems to be an excellent candidate to be used as an optical sensor (UV photodetector) in optoelectronics. [ABSTRACT FROM AUTHOR]