Can Ultrasound or pH Influence Pd Distribution on the Surface of HAP to Improve Its Catalytic Properties in the Dry Reforming of Methane?

The influence of ultrasound and different pH pre-treatments during the metal doping/modification of a hydroxyapatite (HAP) support is investigated. HAP is first synthesised via a hard-template synthetic route using carbon nanorods followed by their full physiochemical characterisation. The HAP was found to be crystalline and comprised a mesoporous structure as observed via XRD and nitrogen adsorption with a BET surface area of 97.57 (±1.16) m2 g−1. Ultrasound-assisted ion exchange (IE) and incipient wetness impregnation (IW) methodologies were employed to decorate the surface of HAP with Pd0 and are compared to previous procedures. The influence of pH upon the distribution of Pd0 throughout the samples during the doping process is also studied. All the prepared samples were evaluated for their catalytic activity towards dry reforming of methane (DRM) and the reaction was monitored via a thermal conductivity detector, coupled with gas chromatography (GC-TCD). It was found that ultrasound-assisted IE significantly accelerated the process from 3 days to 3 h and with the Pd0 metal remaining highly distributed upon the HAP with minor changes in catalytic conversions. Moreover, the ultrasound-assisted IW method successfully improved the Pd0 distribution and catalytic performance. On the other hand, the dispersion of the metal was unaffected after pH treatments in IE with no catalytic improvements observed, in contrast to IW, where considerable increase in metal distribution and subsequently catalytic performance was observed

Parthenium hysterophorous flower template assisted SnO2 nanostructure as photoanode for dye sensitized solar cell

The synthesis process of tin oxide (SnO2) nanostructures and the performance of alizarin-based SnO2 dye-sensitized solar cells have been investigated in the current work. For the first time, tin oxide nanostructures with various pH values are synthesized using the template taken from parthenium hysterophorous flower which acts as the photoanodes. SnO2 film coated with alizarin dye, a platinum counter electrode, and an iodine electrolyte are used to fabricate DSSC. The structural, morphological, and optical characteristics of the SnO2 nanostructures are investigated using powder X-ray diffraction (XRD), scanning electron microscopy (SEM), photoluminescence (PL), attenuated total reflectance (ATR) spectra, and UV–visible spectroscopy techniques. Current density-voltage (J-V) parameters are measured using electrochemical workstation with solar illumination

Copper(II) oxide on aluminosilicate mediated Heck coupling of styrene with aryl halides in water

CuO/aluminosilicate has been found to be an efficient catalyst for the aqueous Heck coupling of styrene with aryl halides under ligand free conditions. The catalyst (CuO/aluminosilicate) was prepared from CuCl<sub>2</sub>·6H<sub>2</sub>O, aluminium nitrate and tetraethyl orthosilicate (TEOS) and characterized by XRD, HR-TEM, SEM-EDX and XPS. The reaction conditions were optimized with different solvents, bases, catalyst amounts and temperatures using sytrene and 4-chlorobenzonitrile as a model system. The scope of the reaction was subsequently extended to include various substituted aryl halides. Regioselectivity, heterogeneity and reusability were performed