الفهرس 
Introduction and literature surveyOnly 14 pages are availabe for public view
 |  | from | 176 |  |  |
| | | from | 176 | | |
Abstract
In conclusion, nanosized pure nickel cobaltite, 10, 20, and 30 % Ni- nickel cobaltite were successfully fabricated by using the hydrothermal method. The pure nickel cobaltite nanoparticles were successfully doped with Ni. The prepared nano-particles are used as electrodes for the degradation of methanol depending upon the electrochemical activity of pure NiCo2O4, 10, 20, and 30 % nickel-nickel cobaltite (Ni-NiCo2O4). The obtained results reflected the higher effect of using nickel. The stability of the synthesized electrodes was studied, and the result showed the high stability of the prepared catalysts.
In order to optimize the Ni ratio used and totally understand their effect when attached to the pure nickel cobaltite surface, 0.25, 0.5, and 1 % Ni- nickel cobaltite were successfully fabricated by using the same hydrothermal technique. A high anode current density of 105 mA/cm2 was obtained in the case of 1 % Ni-NiCo2O4 at 60 mV/s and 2 M of MOH with high stability of 90.6% current retention after 100 hundred repeated cycles. This result reveals the great effect of Ni metal when deposited over NiCo2O4 surface with the proper ratio.
Pure PbS and lanthanum doped PbS thin films have been fabricated by the spray pyrolysis technique at temperatures of 450 and 500 °C, with a doping concentration ratio of 1, 5, and 10% for La. The sensor materials have been exposed to the target gases with a concentration of (200 ppm) mixed with a certain amount of dried air The sensing performance of the films have been tested at temperatures of 50, 80, 120, and 150 °C where it was found that doping increases the sensitivity of the PbS thin film. The synthesized materials showed comparable activity to other sensing materials prepared in different synthetic ways. All films have a large surface area and good sensing behavior near room temperature without the need to apply external voltage to enhance the movement of the electron.