Zinc oxide (ZnO) is a versatile material widely used in optoelectronic devices due to its broad bandgap (3.37 eV), high electron mobility, and significant exciton binding energy (60 meV). In this study, ZnO thin films were fabricated on SiO₂/Si substrates via thermal evaporation, followed by annealing at 400 °C and 600 °C to investigate the effect of thermal treatment on their structural, optical, and photoconductive properties. X-ray diffraction (XRD) analysis confirmed the formation of the hexagonal wurtzite ZnO structure, with improved crystallinity observed at higher annealing temperatures. The photoconductivity of the films demonstrated enhanced response times and self-powered behavior, particularly in the sample annealed at 600 °C. These findings highlight the potential of ZnO thin films for fast-response photodetection applications and show that controlled annealing significantly influences photosensitivity.
9 May 2024 in International Journal of Hydrogen Energy
Herein, we aimed to obtain NiFe layered double hydroxide (LDH) with a controlled phase and surface morphology as a highly active and stable oxygen evolution catalyst via the electrochemical deposition method, which was thermodynamically stable for the oxygen evolution reaction (OER) in an alkaline medium. The NiFe-LDH sample was analyzed by sophisticated instruments and tested as an electrocatalyst on Toray carbon (TC). The NiFe-LDH electrocatalyst showed an excellent performance with lower overpotential of 0.27 V at 35 mA cm−2 and higher density of 125 mA cm−2 for OER in the 1 M KOH electrolyte solution. Moreover, the prepared catalyst exhibited unpredictable long-time stability for 700 h. From our knowledge, NiFe-LDH is a robust highly stable electrocatalyst compared to the recent reports.