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Ammonium dihydrogen phosphate (ADP) (NH 4 H 2 PO 4 ) single crystals were grown by gel method using sodium metasilicate (SMS). The X-ray diffraction analysis of the as-grown ADP crystals showed that it possess tetragonal structure having lattice parameters a = 7.502 °A and c = 7.554 °A. The Fourier transform infrared spectroscopy (FTIR) of as-grown ADP crystal taken between wave-number 400 to 4000 cm -1 showed peaks due to vibration and stretching of functional group O-N=P and -ONO 2 in 485 to 902 cm -1 , P=O and O-H in 1076 to 1544 cm -1 and O-H and N-H in 2400 to 3371 cm -1 range. The UV-Vis-NIR spectroscopy of ADP crystal showed direct optical bandgap of 4.99eV and indirect optical bandgap of 4.12eV. The optical microscopy employed to study the surface microstructure showed hillocks on the as-grown surfaces arising due to local increased supersaturation. The thermal properties of the as-grown ADP crystals were studied by thermogravimetric analysis (TGA). The thermal activation energy determined from the TGA curve using Broido, Piloyan-Novikova (PN) and Coats Redfern (CR) relations were in good agreement with each other. The obtained results are discussed in details.

Tin monosulphide (SnS) nanoparticles were synthesized by simple chemical method at ambient temperature. Stannous chloride (SnCl 2 · 2H 2 O) was use as a source for Sn +2 ions and sodium thiosulphate pentahydrate was used as a source for S −2 ions. The energy dispersive analysis of X-ray (EDAX) and X-ray photoelectron spectroscopy (XPS) techniques were used for stoichiometric characterization of the synthesized nanoparticles. While, structural characterization was done by X-ray diffraction (XRD). The particles size was determined from XRD using Scherrer's formula and Hall-Williamson plot. Optical absorption spectrum obtained by spectrophotometer showed sharp absorption edge at 520 nm, which acknowledged the occurrence of blue shift. The photoluminescence (PL) spectra of synthesized SnS nanoparticles for two excitations at 450 nm and 500 nm showed sharp emission peak at 825 nm. The transmission electron microscopy (TEM) image showed spherical shape of the synthesized SnS nanoparticles. The morphology of the synthesized nanoparticles was investigated employing scanning electron microscopy (SEM). The obtained results are discussed in details. Synthesis and Characterization of Tin Monosulphide NanoparticlesChaki et al.

This paper explores the catalytic action of as-synthesized CuAlS 2 microparticles and nanoparticles on cellulose pyrolysis. The CuAlS 2 microparticles were synthesized by heating precursor elements at high temperatures in an evacuated quartz ampoule. CuAlS 2 nanoparticles were synthesized at ambient temperature by using a simple wet chemical technique. Before using the microparticles and nanoparticles for catalytic study, they were comprehensively characterized. The thermal analysis, including catalytic study of both the CuAlS 2 microparticles and nanoparticles on cellulose pyrolysis, was carried out by thermogravimetric (TG), differential thermogravimetric (DTG) and differential thermal analysis (DTA) techniques. Prior to studying their role as catalysts in cellulose pyrolysis, the CuAlS 2 microparticles and nanoparticles were characterized by thermal analysis in an inert N 2 atmosphere. The TG analysis of as-synthesized CuAlS 2 microparticles and nanoparticles showed three and five steps of decomposition, with total weight losses of 6.89% and 53.37%, respectively. The TG analysis of pure cellulose and cellulose mixed with 10%, 5% and 2.5% CuAlS 2 microparticles and nanoparticles demonstrated that the nanoparticles are better catalysts in cellulose pyrolysis than the microparticles. The TG analysis results of cellulose pyrolysis have been supported by the DTA and DTG curves recorded simultaneously. The obtained results are explored in detail.