2 research outputs found
Nanocomposites of CdS Nanocrystals with Montmorillonite Functionalized with Thiourea Derivatives and Their Use in Photocatalysis
Nanocomposites of CdS were prepared in refluxing DMF
using a montmorillonite
organofunctionalized with thiourea derivatives, with different proportions
of the matrix relative to Cd<sup>2+</sup> ions. The matrix provided
sulfur atoms for CdS formation as well as specific binding sites for
systematic anchoring of the nanocrystals. However, addition of thiourea
to the reaction medium was required in order to yield cubic CdS nanocrystals,
and increasing the thiourea/Cd<sup>2+</sup> molar ratio led to the
formation of mixtures of cubic and hexagonal CdS. The samples obtained
using a thiourea/Cd<sup>2+</sup> ratio of 2, with cubic CdS, exhibited
photoluminescence due to both direct recombination and surface trap
states. The distribution of CdS throughout the matrix was characterized
by the presence of aggregates (with diameters in the region of 50
nm) of nanocrystals (with diameters less than 7 nm) on the outer surface
as well as small pillars in the interlayer region. The photocatalytic
performance of the nanocomposites was tested in the degradation of
Rhodamine 6G under sunlight irradiation, with promising results in
terms of degradation time and degree of mineralization