Discipline: Nanoscience or Materials Science
Kevin D. Correa Vargas - University of Puerto Rico at Mayaguez
Co-Author(s): Josian Luciano-Velazquez, University of Puerto Rico at Mayaguez; Veronica I. Nash-Montes, University of Puerto Rico at Ponce; Sonia J. Bailón-Ruiz, University of Puerto Rico at Ponce.
Extensive withdrawal of water in textile and dyeing industries is responsible for the depletion of groundwater at an alarming rate. In his perspective, nanotechnology because of its manipulation of the things at nanometre scale, has promoted the treatment of wastewater using nanomaterials as quantum dots (QDs). Zinc QDs have gained a great attention due to their chemical stability, high absorption coefficients, tuneable optical properties, and their capacity to promote the generation of reactive oxygen species (ROS) in aqueous matrices. ZnS nanoparticles (NP’s) can absorb electromagnetic radiation and generate photo-excited materials which would be generating ROS directly in aqueous phase and destroying organic pollutants by photocatalytic oxidation. Previous studies had evidenced that the catalysts with high surface area evidence more efficiency. In this way the quantum dots, because of their small size ranged between 2 nm to 12 nm, have high surface areas promoting ROS generation and subsequent degradation of the pollutants. Based on the above considerations, this research was addresses on the generation of small nanoparticles (i.e., zinc sulphide) as photocatalytic platform to destroy organic contaminants in aqueous matrices. The objectives were: 1) synthesize ZnS nanoparticles following a reflux method; 2) determine the crystalline structure, composition, and morphology of the nanoparticles, and 3) study the zinc sulphide photocatalytic properties. Cubic structures with high crystallinity were observed on the electron diffraction analyses. The quantum dots size was estimated at lower than 5 nm and the chemical composition studies confirmed only the presence of zinc and sulphur as main components. Optical properties findings evidenced an absorption peak at 310 nm and a luminescent peak at 440 nm, respectively. Catalytic properties of quantum dots were evaluated in presence of organic contaminants like the azo dye Amaranth and different concentrations of QDs (250 and 500 ppm). As-synthesized nanostructures (ZnS QDs) degraded Amaranth dye successfully (86%) after 120 minutes of irradiation with UV-light.
Funder Acknowledgement(s): NSF Grant # HRD-1906130
Faculty Advisor: Sonia J. Bailón-Ruiz, Ph.D., firstname.lastname@example.org
Role: Synthesized ZnS nanoparticles. Characterized ZnS with Spectrophotometer, Spectrofluorometer and TEM. Prepared calibration curve of Amaranth dye solutions. Used photocatalytic properties to degrade Amaranth dye.