Materials Research Bulletin, Vol.62, 122-131, 2015
Influence of sodium dodecyl sulfate concentration on the photocatalytic activity and dielectric properties of intercalated sodium dodecyl sulfate into Zn-Cd-Al layered double hydroxide
Sodium dodecyl sulfate (SDS) has been successfully intercalated into Zn-Cd-Al-LDH precursor with different SDS concentrations (0.2, 0.3, 0.4, 0.5 and 1 mol L-1) using the coprecipitation method at (Zn2+ + Cd2+)/Al3+ molar ratio of 13 and pH 8. The structural, morphological, texture and composition properties of the synthesized (Zn-Cd-Al-LDH-DS) nanostructure were investigated using powder X-ray diffraction (PXRD), scanning electron microscope (SEM), thermogravimetric analysis (TGA) and Fourier transform infrared (FT-IR), respectively. The photocatalytic activity of these materials was developed by increasing the concentration of intercalated SDS. The absorbance spectra have been used to detect an anion in the LDH interlayer before and after the intercalation process, which confirmed the presence of the dodecyl sulfate (DS-) anion into LDH gallery aftet intercalation. The anomalous low frequency dispersions(ALFD) has been used to describe the dielectric response of Zn-Cd-Al-LDH-DS nanostructure using the second type of universal power law. At low frequency, the polarizatien effect of electrodes caused the rising in dielectric constant and loss values. An important result of the dielectric measurements is the calculated dc conductivity values, which are new in dielectric spectroscopy of LDH materials. An important result of the electron spin resonance (ESR) spectra exhibited the successful intercalation of DS molecule into LDH gallery. The g-factor value was affected by the SDS concentration which indicated changes to the environment around the DS molecule in LDH interlayer. (C) 2014 Elsevier Ltd. All rights reserved.
Keywords:Layered compounds;Intercalation reactions;X-ray diffraction;Thermogravimetric analysis;Dielectric properties;Electron spin resonance