Teresa Zayas

Effect of Sn precursor on the synthesis of SnO2 and Sb-doped SnO2 particles via polymeric precursor method

SnO2 and Sb-doped SnO2 particles were synthesized using the polymeric precursor method with different Sn salt precursors: SnCl2·2H2O, SnCl4·5H2O, or Sn citrate. Sb2O3 was used as the precursor of Sb, and the molar ratio of nSn:nSb was held constant. FTIR and TGA/DTA were used to examine the influence of the Sn precursor on the formation and thermal decomposition of the Sn and Sn-Sb complexes. The calcination products obtained from heating the Sn and Sn-Sb complexes at 500°C in air were analyzed using XRD and TEM analysis. The results revealed that the SnO2 and Sb-doped SnO2 formation temperatures depended on the nature of the Sn precursor. The calcination products were found to be SnO2 and Sb-doped SnO2 particles, which crystallized in a tetragonal cassiterite structure with a highly preferred (110) planar orientation. The Sn precursor and the presence of Sb in the SnO2 matrix strongly influenced the crystallinity and lattice parameters.

Crystal and molecular structure of o-methacryloylaminophenylarsonic acid

AbstractThe title compound, o-methacryloylaminophenylarsonic acid (o-MAPHA), C10H12AsNO4, is a monomer used to obtain water-soluble polyelectrolytes. It was obtained from the condensation reaction of o-arsanilic acid and methacryloyl chloride. Crystallization from aqueous ethanol solution yielded colorless prismatic crystals, and one was used for X-ray analysis. The crystal structure was solved using direct methods with a refined R1 = 0.0483. The crystal structure belongs to the triclinic system, space group

Enzymatic treatment of wastewater from the corn tortilla industry using chitosan as an adsorbent reduces the chemical oxygen demand and ferulic acid content

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Cyclic voltammetry and electrochemical quartz crystal microbalance studies of a rhodized platinum electrode in sulfuric acid solution

, and the asymmetric unit comprises two molecules of the o-MAPHA acid and one water molecule. Both acid molecules are approximately planar and in both molecules the As atom presents common tetrahedral geometry with two long As–O bonds for hydroxyl groups and one short As–O bond for the oxo groups. The structure of o-arsanilic acid (o-ARSA), C6H8AsNO3, was also determinated using the same methods and compared with the o-arsanilic acid structure previously reported. The crystal structure of the o-arsanilic acid belongs to the monoclinic crystal system and to the P21 noncentrosymmetric space group with Z equals two.