Development of Heterostructured Ferroelectric SrZrO3/CdS Photocatalysts with Enhanced Surface Area and Photocatalytic Activity

This paper reports the attempt to develop an efficient heterostructure photocatalyst by employing SrZrO 3 as ferroelectric substrate with deposited nanostructured CdS semiconductor on the surface. Primarily bare SrZrO 3 and CdS nanoparticles were synthesized by using polymeric citrate precursor and co-precipitation routes, respectively. The chemical deposition technique was used to develop the CdS over the surface of the pre-synthesized SrZrO 3 nanoparticles. The synthesized bare nanoparticles and their heterostructure were characterized by XRD which shows the formation of orthorhombic and face centred cubic (FCC) phases of SrZrO 3 and CdS, respectively. TEM was used to estimate the morphology and particle size of as-synthesized nanoparticles, which shows the average particle size of 14, 24 and 25 nm for SrZrO 3 , CdS and SrZrO 3 /CdS, respectively. The BET surface area of SrZrO 3 , CdS and SrZrO 3 /CdS samples was found to be 299, 304 and 312 m2/g respectively. Methylene blue was used as model pollutant to determine the photocatalytic activity of the synthesized nanomaterials. The heterostructure shows an enhanced activity as compared to bare nanoparticles. Dielectric constant and dielectric loss of the nanoparticles was investigated as a function of frequency at room temperature and as a function of temperature at 500 kHz. The room temperature dielectric constant for SrZrO 3 , CdS and SrZrO 3 /CdS was found to be 13.2, 17.8 and 25.5 respectively at 100 kHz.