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Materials for Nanosensors
Published in Vinod Kumar Khanna, Nanosensors, 2021
What are nanoporous materials? Nanoporous materials are those having pore sizes less than 100 nm. Such materials are found in abundance in the natural world, both in biological systems and natural minerals. The walls of animal cells are made of nanoporous membranes. The petroleum industry has long used nanoporous materials called zeolites (microporous, aluminosilicate minerals) as catalysts (Sun et al. 2008). Aerogels are highly porous materials manufactured with the lowest bulk density of any known porous solid. They can have densities as low as four times that of air. They are derived from a gel whose liquid component has been replaced with a gas. For silica aerogels, the distribution of pore sizes has a peak of around 5 nm radius. Activated carbon, a form of nanoporous carbon, is another interesting material. Advances in the capacity to view and manipulate material at the nano level have enabled the directed design of nanoporous materials, rather than to exploit their opportunistic availability. The main research challenges in nanoporous materials include the fundamental understanding of structure-property relationships and the tailor-made design of nanostructures for specific properties and applications.
Introduction and Literature Review
Published in It-Meng Low, Hani Manssor Albetran, Victor Manuel de la Prida Pidal, Fong Kwong Yam, Nanostructured Titanium Dioxide in Photocatalysis, 2021
It-Meng Low, Hani Manssor Albetran, Victor Manuel de la Prida Pidal, Fong Kwong Yam
This method is called the template method because the pores in the nanoporous membranes are used as templates. The template method is an old approach and a classic bottom-to-up method, which has become extremely popular since the last decade [154]. The template is particularly suitable for the generation of thin films and powders with a well-defined porosity. Moreover, the template synthesis uses a nanoporous membrane as a template to make nanofibers, nanowires, and nanotubes. The most important feature of this method is that tubes and fibers composed of electronically conductive polymers and semiconductors can be prepared in a nanostructure such as titania nanotubes and nanofibers [155]. Although the template is a directed method that provides a straightforward and reliable stratagem for processing 1D nanostructured TiO2 , it involves multiple (at least three) steps: template fabrication, filling or coating of the template surface with titania precursor, and the selective removal of templates [123].
Dimensionality Transformation of Layered Materials toward the Design of Functional Nanomaterials
Published in Kazuhiro Shikinaka, Functionalization of Molecular Architectures, 2018
Nanostructured materials, such as nanoparticles, nanorods, nanosheets, and nanoporous materials, are of great importance for the development of nanotechnology [1]. Nanoparticles have unique nano-size effects, and nanoporous materials can be used for materials storage, materials transport, and reaction fields. Dimensionality of nanostructures provides a useful viewpoint toward nanostructural design of materials (Fig. 4.1). For example, zero-dimensional (0D) nanoparticles have quantum-well potential in all axes, providing remarkable nano-size effects, such as localized surface plasmon and superparamagnetism [2, 3]. One-dimensional (1D) nanorods/wires and two-dimensional (2D) nanosheets have characteristic charge transport properties [4]. Three-dimensional (3D) materials have good mechanical properties, compared with low-dimensional materials, because of their robust framework, and they are useful as catalyst supports, separation media, adsorbents, and so on [5].
The emergence of nanoporous materials in lung cancer therapy
Published in Science and Technology of Advanced Materials, 2022
Deepika Radhakrishnan, Shan Mohanan, Goeun Choi, Jin-Ho Choy, Steffi Tiburcius, Hoang Trung Trinh, Shankar Bolan, Nikki Verrills, Pradeep Tanwar, Ajay Karakoti, Ajayan Vinu
Pores can be introduced in inorganic materials through the hard templating process in which porous scaffolds are used as templates. Mostly, nanoporous materials with 2D and 3D porous structures prepared using SDAs are used as the hard templates. Various methods such as impregnation, adsorption and pore-filling are adopted for filling the pores in the template with the required silica or other precursors [121]. The removal of the template following the pore filling and further processing yields the final structure of the material. Silica, metals, metal oxides, carbon, polystyrenes, calcium carbonate (CaCO3) are generally used as the hard templates for obtaining various nanoporous structures wherein the morphology, pore size and size of the nanoparticles can be controlled by varying the morphology, the pore size and the particle size of the hard templates (Figure 1C) [116,122–124]. Multiple novel mesoporous materials including boron nitride, boron carbon nitride, carbon nitrides, metal nitrides, polymers, fullerenes [124–133] and biomolecules in addition to silica and carbon have been prepared using mesoporous carbon or silica as templates [124,134], revealing the versatility of the process of hard templating.
Mn2O3 nanoparticle impregnated glycine max husks for the optimization of oil remediation in contaminated water
Published in Journal of Environmental Science and Health, Part A, 2022
Ikeokwu Ogbu, Cynthia Ibeto, Assumpta Chinwe Nwanya, Chukwuma Okoye
Treatment of sorbent by the impregnation of nanoparticles from metal oxides into it[9] is among one of the most recently applied modification methods that have improved the abstraction of oil in contaminated water surfaces. Nano materials are materials that have pores below 100 nm in size, which are usually similar to the dimension of individual molecules. Nanoporous materials are multipurpose and can be employed in a multiplicity of industrial applications, including sorption, catalytic reactions and many environmental treatments, owing to the existence of voids of manageable dimension within the molecular, atomic, as well as nanometer scales.[10] In addition, their improved surface area and high porosity make them suitable for sorption of oil.
Synthesis of MTW@MOF nanocomposite for removal of methylene blue
Published in Journal of Coordination Chemistry, 2021
Azita Albouyeh, Afshin Pourahmad, Hassan Kefayati
Zeolites and MOFs are two important examples of nanoporous materials. Zeolite and MOFs have common specifications of high surface areas and uniform micropores and differ in thermal/mechanical stability and structural flexibility. The integration of MOFs and zeolite into composite particles is envisaged to produce useful hybrid nanoporous materials where inorganic zeolite and organic MOF components transmit the advantages of high thermal, mechanical and structural stability of zeolites and specific functionality and high flexibility of MOFs [15]. There are a few reports on zeolite@MOF composites [16–19]. Recently, we reported synthesis of Zeolite Y @ MIL-53 (Al) core@shell [20], with modifying of zeolite Y surface with COOH groups. In this study, Zeolite Socony Mobil-12 (ZSM-12) and MOF-74 were chosen as components in the zeolite@MOF core@shell for photodegradation of MB as a cationic dye. RHS was used as a silica source for ZSM-12 zeolite synthesis [21]. Zn-MOF-74 is a typical MOF with high density of metal sites and high stability for heterogeneous catalysis [22]. MOF-74 (Zn) has been chosen as the target photocatalyst owing to its stability, low cost, nontoxic nature and visible light response [23]. MOF-74 (Zn) containing transition metals as structural nodes are expected to be semiconductors since the empty d metal orbitals mixed with the LUMOs of the organic linkers form the conduction band [24]. Herein, we report the photocatalytic activity of ZSM-12@MOF-74 (Zn) in photodegradation of MB dye.