The effect of different pH modifier on formation of CdS nanoparticles

CdS nanoparticles were prepared by hydrothermal method. The effects of pH modifier on the properties of CdS particles were studied. NaOH and NH4OH were chosen as the pH modifier. The morphology and optical properties of CdS particles were characterized by transmitted electron microscope (TEM) and optical absorption spectra analysis, respectively. The particle size of the samples whose pH modifier is NaOH was smaller than that of the CdS samples with NH4OH at the same pH value. Optical absorption edge of CdS shifted to longer wavelength with increasing pH value. Optical absorption edge of the samples with NH4OH as pH modifier shifted to the longer wavelength more significantly than that of those samples with NaOH as pH modifier. When CdS particles were adsorbed to the TiO2 electrodes, the photoelectrochemical property of CdS-sensitized TiO2 electrode showed that the samples with NH4OH as pH modifier had higher photocurrent than those samples with NaOH.