Improved photoelectrochemical sensitivity of Al-doped ZnO nanostructure prepared by co-precipitation and spin-coating techniques

•Al:ZnO films were synthesized by coprecipitation and spin-coating techniques.•Al doped ZnO films showed an important optical properties.•Al doped ZnO nanostructure enhanced the photoconductivity.•Fewer Al doping content showed a better photocurrent response. In this paper we report on co-precipitation and spin-coating process to synthesize pure and aluminum (Al) doped nanostructured zinc oxide thin layers. X-ray diffraction (XRD) technique was involved to investigate the crystalline properties of prepared layers. XRD analysis indicated that the films were indexed as the hexagonal phase of wurtzite-type structure. Al doping revealed a significant effect on the optical measurements, where the band gap has been shifted from 3.22 eV for pure ZnO film to 3.27 eV after Al doping. Additionally, among all photo-anodes with different Al dopant concentrations, the sample with 1 at.% Al:ZnO film exhibited the fastest response and highest photoconduction sensitivity.