Thermally Stable, Thin, Ultralight, Reusable, and Flexible Multiwalled Carbon Nanotube Membranes for Removal of Heavy Metals, Polycyclic Aromatic Hydrocarbons, and Particulates from Coal Smoke

Abstract

Rapid industrialization, haphazardous urbanization, and ruthless burning of fossil fuel have alarmingly impacted human health and the environment. The majority of health issues, such as asthma, cardiovascular disease, and cancer, are primarily associated with polyaromatic hydrocarbons (PAHs), particulate matter (PM), nickel (Ni) and cadmium (Cd) heavy metals, and other contaminants. To address these challenges, the development of an efficient air filtration unit to remove the toxic substances from the smoke is a necessity. The majority of the recently developed air filters are architecturally monotonous and bulky and suffer from a trade-off between removal effectiveness and air permeability. Herein, we have proposed an air filter which is scalable, ultralight (∼0.0034 g), thin (∼50 μm), thermally stable (∼500 °C), hydrophobic (contact angle 138° ± 6°), and porous (porosity of ∼57%) with a pore size of ∼16 nm and has an effective packing density of ∼0.64 g/cm3. The self-assembled nanoarchitecture network (nanonetwork) air filter has a relatively lower pressure drop (∼133.3 Pa) and can remove ∼99%, ∼99%, and ∼90% and 50% for PAHs, PM, and Ni and Cd heavy metals, respectively. This research will be highly beneficial for designing and developing high-performance fibrous materials for filtering and separation applications.

Geometric Transformation of Modified Multiwalled Carbon Nanotubes-Based Heterometallic Nanostructured Material: A Model for the Electrochemical Discrimination of Insecticides

“…Therefore, modification of MWCNTs by different materials such as metal nanoparticles, metal oxides, and organic ligands tends to open up these bundles and make them dispersible in different solvents. − Song et al synthesized a hybrid containing FeCo bimetallic organic frameworks, a melamine mixture, and bamboo-like N-doped CNTs, entangled with N-doped carbon nanosheet nanocomposites (FexCoy–N–C), which shows an outstanding oxygen reduction reaction performance in alkaline medium by the synergistic effect . Moreover, materials containing heterometal having application in homogenous catalysis, electrocatalysis, excellent electrical conductivity had also been reported. , In particular, noncovalent immobilization of polyaromatic hydrocarbons such as the pyrene moiety on the sidewall of MWCNTs via π–π interactions was reported as a straightforward strategy. − The CNTs functionalized with small organic molecules or polymer-based molecules have been utilized for increasing the dispersibility as well as surface area of MWCNTs via π–π interactions, van der Waals interaction, and electrostatic interaction. − The modification mainly intensifies the conductivity of MWCNTs by providing more electron transfer and making it a more advantageous nanomaterial for electrochemical studies. , The modification of MWCNTs with heterocomplexes manipulates the properties of the combined material and provides an excellent electrochemical activity . Novel strategies for the development of new materials as well as improving the electrocatalytic activity and stability of current materials are greatly desired .…”