Discipline: Technology and Engineering
Subcategory: Environmental Engineering
Zachary Shepard - Assumption College
Co-Author(s): Arvid Masud, University at Buffalo, Buffalo, NY; Nirupam Aich, University at Buffalo, Buffalo, NY
Iron nanoparticles have frequently been applied as a treatment method for heavy metal and organic pollutants. These particles are effective because of their redox activity and large surface area to volume ratio. The large surface area is compromised when the nanoparticles’ magnetic properties cause aggregation. Molybdenum disulfide, MoS2, can act as a scaffold for the iron nanoparticles, preventing aggregation and increasing available surface area. Here, we report the synthesis of a MoS2/iron nanoparticle hybrid and application for the remediation of methylene blue, a model organic contaminant. An analysis of three exfoliation methods (lithiation, sonication in 45% volume ethanol/water, and sonication in n-methyl-2-pyrrolidinone) was undertaken to determine the safest and most environmentally-friendly synthesis of few-layer MoS2 nanosheets. Exfoliated products were analyzed with ultraviolet-visible spectroscopy, Raman spectroscopy, and HRTEM. Sonication in ethanol/water was found to be the safest and most sustainable method for the production of MoS2 sheets. The MoS2/Fe compound was synthesized with different iron: MoS2 ratios (1:1 and 1:2) using ultrasonic spray pyrolysis. Characterization with Raman spectroscopy and HRTEM confirmed iron nanoparticles were embedded on MoS2 nanosheets. Adsorption experiments were carried out with exfoliated MoS2 nanosheets and nanohybrids used to treat a solution of methylene blue. Preliminary results indicated that the adsorption by the nanohybrid was slightly improved compared to bulk MoS2. In the future, we hope to improve the yield of the nanohybrid and perform more rigorous testing of its adsorption capabilities.
Funder Acknowledgement(s): National Science Foundation Grant No. 1559989
Faculty Advisor: Nirupam Aich, nirupama@buffalo.edu
Role: I played a role in each aspect of this project. I was tasked with determining the most effective method of exfoliating molybdenum disulfide into few layer sheets and utilizing it to synthesize the iron/MoS2 nanohybrids. The exfoliation of MoS2 and synthesis of the nanohybrids were largely my responsibility. Our research group utilizes ultrasonic spray pyrolysis to synthesize the nanohybrids and our apparatus required constant attention. I also characterized the results of the exfoliation and nanohybrid syntheses using Raman microscopy, dynamic light scattering, and UV Vis spectroscopy.