Annealing temperature dependency of structural, optical and electrical characteristics of manganese-doped nickel oxide nanosheet array films for humidity sensing applications

Manganese-doped nickel oxide nanosheet array films are successfully prepared on a seed-coated glass substrate by an immersion method. Various annealing temperatures between 300°C and 500°C applied to the manganese-doped study their effect properties of oxide, including humidity sensing performance. Field emission scanning electron microscopy (FESEM), energy dispersive X-ray spectroscopy (EDS), diffraction (XRD), ultraviolet–visible (UV–vis) spectrophotometry, two-probe current–voltage ( I- V) measurement system used characterise heat-treated samples. The temperature can be clearly observed for different surface morphologies patterns. samples exhibit average crystallite size increases 0.63–10.13 nm with increasing temperature. dislocation density, interplanar spacing, lattice parameter, unit cell volume stress/strain also determined from XRD data. transmittances in visible region all show low percentages highest transparency 50.7% recorded annealed at 500°C. optical band gap shows decreasing trend V results reveal that displays improved conductivity values sensitivity sensors ascending curve optimal device performance is obtained 500°C, 270 fastest response recovery times. In contrast, sample poor