Effect of Acid Treatment in Dye Loading Capacity of Spin Coated ZnO Film

In recent times, the research on ZnO is growing tremendously, because of its potential use in many applications such as optical devices, dye sensitized solar cell (DSSC), gas sensors and biomedical. ZnO thin films of various thicknesses were prepared by the spin coating method using the zinc acetate precursor with diethanolamine and ethanol. The structural and optical characterizations of as-prepared ZnO films carried out using XRD and UV-Vis spectrophotometer, respectively. The XRD results showed polycrystalline wurtzite structure of ZnO. The average crystallite size of ZnO as calculated using Debye Scherrer’s formula was 26 nm. The optical band gap of ZnO was found to decrease with film thickness. The dye extracted from the leaves of Tectona Grandis (Sagun) which possesses a high and wide absorbance was used in this experiment. The study on the effect of acid treatment on ZnO films in dye loading showed enhanced absorbance in acid treated ZnO as compared to untreated ZnO.

New carbon/ZnO/Li2O nanocomposites with enhanced photocatalytic activity

Our study was focused on the synthesis of photocatalytic materials for the degradation of organic dyes based on the valorization of biomass resources. The biochar resulted from pyrolysis process of cherry pits wastes was activated by CO2 flow. Activated and inactivated carbon was used to obtain carbon-based photocatalysts impregnated with different zinc salt precursors. The activation of carbon had no significant influence on the photodegradation process. The doping procedure used Li2CO3 and Zn(CH3COO)2 of different concentrations to impregnate the biochar. The carbon-ZnO-Li2O based nanomaterials were analysed by TEM and SEM, while the presence of hexagonal wurtzite ZnO was investigated by XRD. The solid samples were analysed by PL at 360 nm excitation fixed wavelength to correlate their morphology with the optical and photocatalytic properties. The presence of Li atoms led to photocatalytic activities of the doped ZnO similar to the undoped ZnO obtained at higher concentrations of zinc acetate precursor.

Enhanced bactericidal and photocatalytic activities of ZnO nanostructures by changing the cooling route

Enhanced antimicrobial activity and photocatalytic performance are obtained by the calcination and subsequent rapid cooling of the zinc acetate precursor.

Nanoparticulate Functional Materials: Green Synthesis and Application for the Degradation of Phenolic Compounds

Zinc oxide nanoparticles was synthesized by microwave decomposition of zinc acetate precursor. Horseradish peroxidase (HRP) was immobilized on nano-ZnO. The catalytic activity, physical, and chemical properties of immobilized HRP as well as the interaction between HRP and nano-ZnO was studied. The Nano-ZnO immobilized HRP showed a better property in the thermostability, active pH stability. The Nano-ZnO is more effective than free HRP in the removal of many phenolic compounds. The results show that nano-ZnO is strong functional materials for envrionment protection.

Effect of Aluminum Nitrate Concentration in Zinc Acetate Precursor on ZnO:Al Thin Films Prepared by Spray Pyrolysis

Aluminium-doped zinc oxide (ZnO) films have been prepared by spray pyrolysis technique using the mixed solution of zinc acetate dihydrate and aluminium nitrate nonahydrate in methanol. Concentration of aluminum in the solution was varied in a range of 1, 3 and 5 atomic percents. The results from X-ray diffraction showed that the preferred orientation of ZnO films changed to the [002] direction when the concentration of aluminum in the solution exceeded 1 atomic percents. ZnO films deposited from the 3 atomic percent Al containing solution had the largest grains and showed the lowest resistivity of 75 Ω-cm. Addition of aluminum into the precursor solution shifted the absorption edge towards longer wavelengths.