ABSTRACT
In order to control diesel exhaust emission, CeO2-SnO2/Al2O3 (CTA) mixed oxides were prepared and coated on perforated stainless steel (SS) filter plates, and the catalytic activities were analyzed in this work. The CeO2-SnO2 (different compositions of Ce/Sn-2:8; 1:1; 8:2) composites and Al2O3 were prepared separately via a co-precipitation approach, and CeO2-SnO2/Al2O3 (CTA) mixed oxides were attained by mechanical mixing of 75 wt% CeO2-SnO2 composites with 25 wt% Al2O3. X-ray diffraction (XRD) and Raman spectroscopy were performed for all three CeO2-SnO2/Al2O3 (CTA) mixed oxides; the CeO2-SnO2/Al2O3 (Ce/Sn-1:1) sample confirmed the presence of cubic and tetragonal mixed faces, which enhances the redox nature (catalytic activities). Various characterizations such as high-resolution transmission electron microscopy (HRTEM), Brunauer-Emmett-Teller (BET) analysis, X-ray photoelectron spectroscopy (XPS), and a scanning electron microscope (SEM) were employed on CeO2-SnO2/Al2O3 (Ce/Sn-1:1) sample to investigate the structural, textural, compositional, and morphological properties. The CeO2-SnO2/Al2O3 (Ce/Sn-1:1) sample was coated on a perforated stainless steel (SS) filter plate via a simple, cost-effective, and novel method, and an exhaust emission test for various compression ratios (CR), injection pressure (IP), and load (L) was completed using an AVL Digas analyzer. The CeO2-SnO2/Al2O3 (Ce/Sn-1:1) sample, with a size of 10.22 nm and a high surface area of about 73 m2 g-1, exhibit appreciable catalytic properties.
ABSTRACT
In this work, ZnO nanoparticles were prepared by in situ chemical precipitation method in the presence of Agar biopolymer. The influence of Agar concentrations on the structural, morphological and optical properties of ZnO have been investigated. The XRD pattern of Pure ZnO and Agar/ZnO nanocomposites indicates the hexagonal wurtzite phase of ZnO. The crystallite size of pure ZnO and Agar/ZnO nanocomposites was found to be in the range of 35.5 to 19.73â¯nm. Pure ZnO and Agar/ZnO nanocomposites showed nanospheroid and nanopaddy shaped morphology from FESEM studies. The interplanar distance observed from the HRTEM image confirms the plane of the prepared material. The elemental composition of the samples were characterized by EDX. The optical properties of Pure ZnO and Agar/ZnO nanocomposites were characterized by UV, FTIR and PL. The band gap of Agar/ZnO nanocomposites were varied with the Agar concentration. Oxygen vacancy induced photoluminescence of ZnO are observed and its intensity is found to be increased linearly with the Agar concentration. The antibacterial activity of ZnO and Agar/ZnO nanocomposites was evaluated by disc diffusion method against Gram-positive (B.subtilis) and Gram-negative (P. aeruginosa) bacteria. The cytotoxicity of Agar/ZnO nanocomposites was studied against Normal (L929) and Breast cancer cell line (MB231). The result of this investigation reveals that the Agar/ZnO nanocomposites deliver a dose dependent toxicity in normal and cancer cell line.
