Discipline: Nanoscience
Subcategory: Pollution/Toxic Substances/Waste
Session: 4
Room: Park Tower 8216
Gabriel E. Torres-Mejias - University of Puerto Rico in Ponce
Co-Author(s): Sonia J. Bailon-Ruiz, University of Puerto Rico, Ponce, PR
Since their discovery in the mid 19th century, synthetic dyes manufacturing has grown into a massive industry and has led to major water pollution. Today, an average-sized textile mill consumes about 1.6 million water liters daily, which gets contaminated with a set of chemicals that might be harmful to both the ecosystem and human health. (Kant, 2012) This industry is wasting an extreme quantity of precious and scarce water while contemporary technology as been inefficient as current methods seems unable to degrade completely the pollutant agents. (Mun, 2008) Although, the emergence of advanced oxidation process has given rise to intriguing methods such as photocatalyst semiconductors (i.e. ZnO) that can be applied to degrade dyes in aqueous solution. (Sobczynski, 2001) Based on this we wanted to study the capacities of ZnS cubical quantum dots (QDs) as photocatalyst on synthetic dyes. To do so, we establish the following objectives: 1) Synthesize ZnS QDs, 2) Characterize their crystalline structure and optical properties, and 3) Test their photocatalytic capacities on Methylene Blue in aqueous solution at different pH and calculate the kinetic parameters for each reaction. ZnS QDs presented a luminescent peak at 446nm and it was evidenced that they possess a cubical crystalline structure and a size below 5nm. Photodegradation experiments on Methylene Blue 15µM were performed under the presence of ZnS QDs at different concentrations (i.e. 250ppm, 500ppm). Future evaluations will proceed with the study of how pH affects the photodegradation capacities of the particles. References: 1. Kant, R. (2012). Textile dyeing industry an environmental hazard. Natural Science, 04(01), 22-26. DOI: 10.4236/ns.2012.41004 2. Mun L. (2008). Degradation of dyes using zinc oxide as the photocatalyst. M.S. thesis. Putra University, Serdang, Malaysia. 3. Sobczynski A. and Dobosz A.(2001).Water purification by photo-catalysis on semiconductors. Polish Journal of Environmental Studies, 10(04), 195–205.
Funder Acknowledgement(s): Institutional Funds of my Advisor, PR-LSAMP and the support of the Department of Chemistry and Physics.
Faculty Advisor: Sonia J. Bailon-Ruiz, Sonia.bailon@upr.edu
Role: I did all the processes involved in synthesis and characterization and also performed the photodegradation experiments. Alongside my Advisor, I analyzed the data and came up with conclusions.