RESUMO
ZnWO4MnPc was synthesized via a hydrothermal autoclave method with 1 wt.% manganese (iii) phthalocyanine content. The material was characterized for its structural and morphological features via X-ray diffraction (XRD) spectroscopy, Fourier transform infrared (FTIR) spectroscopy, transmission emission microscopy (TEM), scanning electron microscopy-Energy dispersive X-ray spectroscopy (SEM-EDX), N2 adsorption-desorption at 77K, X-ray photoelectron spectroscopy (XPS), and UV-visible/diffuse reflectance spectroscopy(UV-vis/DRS). ZnWO4MnPc photocatalytic performance was tested on the degradation of bisphenol A (BPA). The ZnWO4MnPc material removed 60% of BPA after 4 h of 365 nm UV irradiation. Degradation process improved significantly to about 80% removal in the presence of added 5 mM H2O2 after 4 h irradiation. Almost 100% removal was achieved after 30 min under 450 nm visible light irradiation in the presence of same concentration of H2O2. The effect of ions and humic acid (HA) towards BPA removal was also investigated.
RESUMO
The aim of this work was to study the dependence of the optical, structural and morphological properties of CuIn0.7Ga0.3(Se(1-x)Te(x))2 (briefly CIGSeTe) thin films for two different stoichiometries (for x = 0.2 and 0.8). The films have been deposited onto soda lime glass (SLG) substrates by the e-beam evaporation technique. The films showed high absorption and revealed optical band gaps ranging from 1.17 eV to 1.06 eV for x = 0 with highest annealing temperatute at 525 degrees C and 1.12 eV to 1.02 eV for x = 0.8 and with highest annealed temperature at 600 degrees C. These results were correlated with the microstructural analysis by Atomic Force Microscopy (AFM), Scanning Electron Microscopy (SEM) and X-ray diffractometry (XRD). The linear dependence of the lattice parameters as a function of Se and Te contents was examined. X-ray diffraction analyses showed that the films had the single phase chalcopyrite structure. The lattice parameters (a and c) varied linearly with the increase in Te content x from x = 0.2 to x = 0.8. The peak correspondng to the (1 1 2) plane orientation of the films increased with annealing process. Also, SEM images showed that both the grains size and the RMS (root mean square) values increased with annealing and higher Te amount that caused grains aggregation. The relative 600 degrees C elemental composition present in the deposited CIGS films have been measured by using energy dispersive X-ray analysis (EDX).