High Adsorption of Benzoic Acid on Single Walled Carbon Nanotube Bundles

Abstract

Removal of harmful chemicals from water is paramount to environmental cleanliness and safety. As such, need for materials that will serve this purpose is in the forefront of environmental research that pertains to water purification. Here we show that bundles of single walled carbon nanotubes (SWNTs), synthesized by direct thermal decomposition of ferrocene (Fe(C5H5)2), can remove emerging contaminants like benzoic acid from water with high efficiencies. Experimental adsorption isotherm studies indicate that the sorption capacity of benzoic acid on these carbon nanotubes (CNTs) can be as high as 375 mg/g, which is significantly higher (in some cases an order of magnitude) than those reported previously for other adsorbents of benzoic acid such as activated carbon cloth, modified bentonite and commercially available graphitized multiwall carbon nanotubes (MWNTs). Our Molecular Dynamics (MD) simulation studies of experimental scenarios provided major insights related to this process of adsorption. The MD simulations indicate that, high binding energy sites present in SWNT bundles are majorly responsible for their enhanced adsorptive behavior compared to isolated MWNTs. These findings indicate that SWNT materials can be developed as scalable materials for efficient removal of environmental contaminants as well as for other sorption-based applications.

Adsorption of Benzoic Acid: Structural Organization on the Surfaces of Pristine and Functionalized Single-Walled Carbon Nanotubes

“…A separate work that was recently completed tackles the adsorption energy implications of CNT surface curvature in single-walled and multiwalled arrangements. 37 The net surface charge of the current pristine CNT (0% functionalization) is kept neutral by assigning a van der Waals potential only to carbon atoms. However, carboxyl attachments in the other three cases (1%, 5%, and 10% functionalization) induce local electrostatics.…”

Carbon Nanotube Based Robust and Flexible Solid-State Supercapacitor

“…9 This has motivated the usage of nanomaterials such as SC electrodes due to their large specific surface area (SSA). 10 Particularly, carbon-based nanomaterials such as activated carbon, carbon nanofibers, mesoporous carbon, diamond-like carbon, carbon nanotubes (CNTs), graphene, and carbide-derived carbon are used widely. 1,11,12 With the emergence of flexible and portable devices, attention on flexible SCs has increased due to their numerous applications in wearable electronics, smart garments, and so forth.…”

“…In both cases, the surface area of the electrode material of an EDLC, therefore, plays an important role because it can be generally said that the higher the surface area, the higher the capacitance will be . This has motivated the usage of nanomaterials such as SC electrodes due to their large specific surface area (SSA) . Particularly, carbon-based nanomaterials such as activated carbon, carbon nanofibers, mesoporous carbon, diamond-like carbon, carbon nanotubes (CNTs), graphene, and carbide-derived carbon are used widely. ,, …”

The Role of Carbon Nanotube Pretreatments in the Adsorption of Benzoic Acid

“…Recently, some researchers have shown that single-walled nanotubes synthesized by the thermal decomposition of ferrocene (Fe(C 2 H 5 ) 2 ) are able to efficiently remove benzoic acid with higher efficiencies than multi-walled nanotubes. Through simulation studies of molecular dynamics, they have shown that the high efficiency of single-walled carbon nanotubes is attributable to sites with high bonding energy [ 36 ].…”