Effect of sintering temperature on the properties of Cu-Co ferrites prepared by oxalate precipitation method

Polycrystalline Cu-Co ferrite powder was synthesized following oxalate precipitation method. The samples of the compound Cu_0.5Co_0.5Fe₂O₄ were heated at different temperatures in the range of 773-1173 K and were characterized by X-ray diffraction and SEM techniques. The results of XRD show the formation of single-phase cubic spinel structure. The lattice parameter showed a minimum value for the sample heated at 1073 K. It has been observed that grain size increases with the increase in temperature and is maximum (3.2 μm) for the powder sintered at 1173 K.     

Hydrated cement: a promising adsorbent for the removal of fluoride from aqueous solution

The present study was carried out to investigate the potential of cement hydrated at various time intervals for the removal of excess F- from aqueous solution by using batch adsorption studies. The influence of different adsorption parameters, viz. effect of adsorbent dose, initial concentration, pH, interfering ions and contact time were studied for their optimization. It was observed that the adsorbent exhibited reasonably significant F- removal over a wide range of pH. The presence of carbonate and bicarbonate ions in aqueous solution were found to affect the F- removal indicating that these anions compete with the sorption of F- on adsorbent. The equilibrium adsorption data were fitted well for both the Freundlich and Langmuir isotherms and the adsorption capacities were calculated. Comparative studies for F- removal in simulated and field water show relatively higher F- removal in simulated water. XRD and SEM patterns of the hydrated cement were recorded to get better insight into the mechanism of adsorption process. From the experimental results, it may be concluded that HC was an efficient and economical adsorbent for F- removal.     

Photo-electrochemical performance of Cd1−xPbxS (0≤x≤1) thin films

This paper discusses chemical synthesis of Cd_1?xPb_xS (0≤x≤1) thin film layers and their photo-electrochemical properties with special reference to PEC parameters. Previously optimized conditions were used for the deposition. The electrode/electrolyte interfaces were then formed between the Cd_1?xPb_xS thin film layers and a sulphide/polysulphide (1 M) redox couple and investigated through the various photo-electrochemical (PEC) properties to assess suitability to convert solar energy into electrical energy.Increase in short circuit current (I_sc) and open circuit voltage (V_oc) was observed with increased composition and attain maximum at x=0.175. Power conversion efficiency and fill factor were found to be 0.163% and 46.2% respectively for the composition parameter x=0.175.     

Photocatalytic degradation of 3‐nitrobenzenesulfonic acid in aqueous TiO2 suspensions

The photocatalytic degradation of 3‐nitrobenzenesulfonic acid in the presence of solar radiation and artificial UV radiation with suspended TiO₂ was studied in a batch and continuous annular reactor, respectively. The effects of catalyst loading, pH, presence of anions and cations and initial concentration on the rate of photocatalytic degradation were investigated. Concentration–time data were correlated with the rate equation d[C_t=0]/dt = k_rK[C_t=0]/(1 + K[C_t=0]). Studies were carried out to compare the photolytic, photochemical and photocatalytic methods of degradation. Copyright © 2005 Society of Chemical Industry     

Pyrroloquinoline Based Styryl Dyes Doped PMMA,PS, and PS/TiO2 Polymer for Fluorescent Applications

This article presents two highly fluorescent donor-π-acceptor (D-π-A) moieties containing an electron-donating carbazole and phenothiazine donors fused with electron-withdrawing pyrrolo-quinoline acceptor dyes, PQC and PQPT. We also discussed the polymerization and film-forming process of dye PQC and PQPT doped in poly (methyl methacrylate) (PMMA) and polystyrene (PS) polymer to find their optical applications in polymer-based technology. We investigated the fluorescent properties of dyes PQC and PQPT from 0.01 to 1 wt% in poly(methyl methacrylate) (PMMA). We also investigated the changes in the spectrum shape and shift in wavelength with changes in poly(methyl methacrylate) (PMMA), polystyrene (PS), and TiO₂ doped in polystyrene (PS/TiO₂). The analysis of surface morphology of prepared polymer samples was done with the help of a scanning electron microscope. The thermal and photostability of synthesized dyes in poly (methyl methacrylate) (PMMA), polystyrene (PS), and TiO₂ doped in polystyrene (PS/TiO₂) were investigated to get detailed information owing to the application of fluorescent polymers in the field of optoelectronic, nanohybrid coatings in solar concentrators, etc.

Graphical Abstract