Porosity and photocatalytic studies of transition metal doped ZnO nanoclusters

Highly mesoporous self-aggregated nanoclusters of pure and transition metal (Mn, Co and Ni) doped ZnO have been synthesized by refluxing their acetate precursors in diethylene glycol (DEG) medium. It was found that the porous spherical nanoclusters comprised of numerous nanocrystals are fairly stable, well-defined and discrete with hexagonal wurtzite structure. The transition metal ions, Mn, Ni and Co were successfully doped into the ZnO structure and are uniformly distributed in the samples. The presence of pronounced hysteresis loop in N2 adsorption–desorption isotherm curves indicates the 3D intersection network of the pores (predominantly mesoporous in nature). Transmission electron microscopy (TEM) analysis indicates that the pores are irregular in shape and randomly distributed throughout the nanocluster. Furthermore, we have explored the photocatalytic activity of these mesoporus pure/doped ZnO nanoclusters using methylene blue as a model dye. It has been observed that these mesoporous ZnO could be a promising photocatalyst for degradation of organic molecules as compared to transition metal doped ZnO under UV light.