Nirupam Aich (UB) and Jacob Henschen (VU)
Research for Undergraduate Experience
Graphene, a two dimensional nanomaterial with remarkable properties, often requires assembly into three dimensional (3D) macroscopic monoliths while retaining its intrinsic nanoscale properties for different functional applications including contaminant removal from water. Recently, Graphene based aerogel monolithic structures have been pursued for contaminant removal application due to porous structure and mechanical strength. However, conventional synthesis methods are unable to control shape and architecture aerogel assembly, limiting potential application in water treatment devices. In this study, we synthesized a freeze casting method with optimized graphene-oxide polydopamine (GO-PDA) to fabricate GO-PDA aerogels of controllable architecture. This approach involved fabricating molds of desired geometric structure (1 mL cube) through fused deposition model printing. A GO-PDA ink was freeze casted into molds and further freeze dried to obtain GO-PDA aerogels identical to the mold's architecture. Polydopamine contributed to aerogel structure integrity through functionalization of graphene surface due to spontaneous polymerization and providing active contaminant adsorption sites. The mold assisted GO-PDA aerogel exhibited high removal capacity for methylene blue (57.29 [46.49% removal efficiency after 12 hrs], 55.49, and 52.28 mg/g respectively), Evans blue (40.96 mg/g [36.93% removal efficiency after 36 hrs]), lead (51.67 mg/g [48.36% removal efficiency after 6 hrs]), and hexavalent chromium (33.13 mg/g [28.13% removal efficiency after 24 hrs]) from aqueous solution. It also exhibited high removal capacity through recycling and regeneration (3 cycles) for methylene blue (>87% removal). Characterization of GO-PDA aerogels was conducted through Scanning Electron Microscopy, Transmission Electron Microscopy, X-Ray Diffraction Spectroscopy, and Raman Spectroscopy to prove functionality of polydopamine.
Sysouvanh, Daosavanh Daniella; Masud, Arvid Mohammad; and Aich, Nirupam, "Synthesis and Characterization of Graphene oxide Polydopamine Aerogels for Contaminant Removal in Water" (2020). Symposium on Undergraduate Research and Creative Expression (SOURCE). 889.