Vol. 7, Issue 1, Part A (2025)

Nickel-doped ZnO thin films were synthesized using the low-cost chemical bath deposition (CBD) method at room temperature. Structural, morphological and optical properties were analyzed using XRD, SEM with E-DAX and UV-Vis spectroscopy respectively. Gas sensing performance was evaluated for detecting toxic gas like hydrogen sulfide (H₂S). Ni doped ZnO film showed sensing response to H₂S gas at lower operating temperature (200 °C) compared to our previously obtained undoped ZnO film with almond-like morphology prepared by the same method (250 °C). The response time of the sensor ranged between 35 and 75 seconds, while the recovery time varied from 75 to 145 seconds towards H₂s.