Conclusions
From this study, we concluded the successful synthesis of CdO using the green method which is easy, cost-effective, and short technique. Furthermore, the study proved the formation of CdO nanoparticles with irregular sphere like structures of 55 nm particle size. Regarding the hydrogen storage, the results prove that the maximum H2uptake was equal to 2.85 Wt.%H2 at a pressure of 69 bar at 77 K with ∆H=0.62607 KJ/mol H2 and ∆S=3.35697 J/mol H2. K. Moreover, the thermodynamic studies at four different temperatures proves that the maximum H2 uptake could be recorded at a pressure limit of 69-86.2 bar. Meaning that, the temperature change did not have an effect on the weight value, because the pressure change was relatively small, which means that it is possible to reach the highest storage without the need for a low temperature.