Hydrothermal Synthesis of Zinc Cobaltite (ZnCo2O4) Nano Particles for Green Hydrogen Production via Water Splitting by Photocatalysis

Zinc cobaltite (ZnCo2O4) nano particles have been synthesized by hydrothermal method for hydrogen generation by photo catalytic water splitting reactions. To indicate the nano-catalyst’s structure, the samples’ characterization has been implemented using XRD, FTIR, SEM and TEM analysis. The characterization revealed successful synthesis of the ZnCo2O4 nano particles. UV–Vis/DRS examination shows that the ZnCo2O4 nanoparticles, especially (Zn: Co) oxide=(1:1.25) sample exhibited superior visible light capture compared to other samples. The photo catalytic activity of photocatalysts were tested for photocatalytic hydrogen generation. The best rate of hydrogen yield of 19ml H2/g. catalyst/min was produced by the optimum ratio of ZnCo2O4 nano-catalysts, (Zn: Co) oxide=(1:1.25). The nano-catalysts' photocatalytic activity has been slightly diminished by repeated usage, which is an evidence of the catalyst's stability. The reaction temperature effect on the rate constant revealed an apparent activation energy for ZnCo2O4 nanoparticles, (Zn: Co) oxide=(1:1.25) of 14 kJ. mol-1. This is the activation energy needed for the photocatalytic reaction's slowest step. In addition, the effect of scavenger concentration on photo catalytic water splitting reactions for hydrogen production also checked