Arsenic Removal from Contaminated Water Using Three-Dimensional Graphene-Carbon Nanotube-Iron Oxide Nanostructures

Abstract

We report a highly versatile and one-pot microwave route to the mass production of three-dimensional graphene-carbon nanotube-iron oxide nanostructures for the efficient removal of arsenic from contaminated water. The unique three-dimensional nanostructure shows that carbon nanotubes are vertically standing on graphene sheets and iron oxide nanoparticles are decorated on both the graphene and the carbon nanotubes. The material with iron oxide nanoparticles shows excellent absorption for arsenic removal from contaminated water, due to its high surface-to-volume ratio and open pore network of the graphene-carbon nanotube-iron oxide three-dimensional nanostructures.

Microwave synthesis of nitrogen-doped carbon nanotubes anchored on graphene substrates

“…3(c)). Comparing the lithium-ion capacity of our 3-D G-Fe@NCNT composites with iron-decorated graphene (synthesized by our previously reported doughnut method [31]), an almost threefold increase in capacity retention throughout the $146 cycles can be observed indicating that the presence of CNTs not only prevent the restacking of graphene but also circumvent the aggregation of Fe nanoparticles on cycling. Additionally, the presence of nitrogen moieties on the CNTs creates defects in the walls of nanotubes through which lithium ions can diffuse [47] and adhere to the interwall spaces, thereby making the observed lithiumion capacity one of the highest when compared to previously reported graphene-CNT-iron hybrids [32].…”

“…Besides, at high temperatures commonly encountered in the CVD growth of CNT, the chemical interface between the graphene and catalyst may be thermally driven off, causing extensive debonding of catalyst particles from the graphene substrate, which may lead to falling off of CNT. There are some reports on the microwave synthesis of CNTs anchored on graphene substrate either by premixing of microwave-synthesized graphene with CNT [28] or by in situ synthesis of CNTs using expensive ionic liquid precursors and palladium catalysts [29], or by the pop-tube technique [30][31][32]. However, in these reported techniques, only pristine CNTs are synthesized, whereas it is well known that heteroatom-doped carbon nanostructures possess distinct advantages in energy storage applications such as lithium-ion batteries [33], supercapacitors [34], etc.…”

Feasible water flow filter with facilely functionalized Fe3O4-non-oxidative graphene/CNT composites for arsenic removal

“…This is beneficial because As(III) is more toxic than As(V). [23,24]. Therefore, M-G/C provides a longer pathway for water flow than M-G of M-C, which increases the water contact with Fe3O4 removing more arsenic for the same amount of compound ( Fig.…”

“…In addition, after combining CNTs and graphene-based materials to create 3D structures with large specific surface areas these carbon-based nanomaterials can more efficiently remove heavy metals, such as arsenic, through functionalization with larger amounts of metal oxides [23,24]. Functionalizing the surfaces of these carbon-based 3D structures with metal oxides can create an attractive adsorbent for water purification.…”

Removal of As(III) and As(V) from Water Using Magnetic Core-Shell Nanomaterial Fe3O4@Polyaniline

“…Among these technologies, adsorption has been widely studied because it is easy to operate and cost-effective. Many materials have been studied as the adsorbents for arsenic removal from aqueous solutions including magnetite-reduced graphene oxide, graphene oxide-MnFe 2 O 4 magnetic nanohybrids, granular activated carbon based adsorbents, iron based adsorbents, nanoscale zero valent iron, three-dimensional graphene-carbon nanotube-iron oxide nanostructures, DNA aptamers, Fe 3 O 4 nanoparticles, chemically modified sawdust, metal (hydr) oxide coated sand, South African sands, aluminum hydroxide and zeolitic imidazolate framework-8 (ZIF-8) nanoparticles [21][22][23][24][25][26][27][28][29][30][31][32][33][34]. Up to date, the development of new materials for arsenic removal still a hot topic in environmental field.…”