Mesoporous Alumina-Titania Composites with Enhanced Molybdenum Adsorption towards Medical Radioisotope Production

Abstract

This work reports the fabrication of mesoporous Al2O3-TiO2 composites with various contents of TiO2 and their utilization as adsorbents for molybdenum anions with potential application in medical radioisotope production. The increase of TiO2 promotes the deposition of more TiO2 nanoparticles on the surface of the Al2O3 support without altering the original morphology. Furthermore, alumina samples loaded with smaller amounts of TiO2 (Al2O3-2.5% Ti (20.01 mass% TiO2) and Al2O3-5% Ti (34.55 mass% TiO2)) are amorphous in nature. However, at a high loading (Al2O3-10% Ti (63.97 mass% TiO2)), anatase TiO2 becomes the dominant phase, suggesting the extensive coverage of the Al2O3 surface by TiO2 NPs. The TiO2 modification is also observed to greatly increase the surface area from 177 m2 g−1 for pristine γ-Al2O3 to as high as 982 m2 g−1 for Al2O3-5% Ti sample. When employed for molybdenum adsorption, the Al2O3-5% Ti sample displays a higher Mo adsorption capacity (44.5 mg g−1) than Al2O3-2.5%Ti (39.0 mg g−1), Al2O3-10%Ti, (40.5 mg g−1), and pristine γ-Al2O3 (37.1 mg g−1) samples. The larger surface area and presence of additional hydroxyl groups for attracting the molybdenum anions contribute to the enhanced adsorption capacities of the Al2O3-TiO2 composites compared to that of pristine γ-Al2O3.

Role of urea on the structural, textural, and optical properties of macroemulsion-assisted synthesized holey ZnO nanosheets for photocatalytic applications

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“…Understanding the surface area and porosity of nanomaterials is key to understanding their quality and utility. 69 Specifically, a larger surface area and pore volume are beneficial for increasing the number of available active sites for various catalytic reactions. 70,71 The N 2 adsorption-desorption isotherms (Fig.…”

Porous carbon nanoarchitectonics for the environment: detection and adsorption

“…88,89 Nanoporous materials are synthesized by template synthesis via self-assembly, dimension-controlled complex formation, and chemical reactions to have a precise pore structure at the nanolevel but in bulk size quantities. They have been actively studied as mesoporous materials, 90,91 metal-organic frameworks (MOFs), [92][93][94] and covalent organic frameworks (COFs). [95][96][97] Sol-gel synthesis provides various porous materials such as macroporous silicone materials that are useful for various applications, including materials separation media and heat insulation.…”

“…88,89 Nanoporous materials are synthesized by template synthesis via self-assembly, dimension-controlled complex formation, and chemical reactions to have a precise pore structure at the nanolevel but in bulk size quantities. They have been actively studied as mesoporous materials, 90,91 metal–organic frameworks (MOFs), 92–94 and covalent organic frameworks (COFs). 95–97…”

Molecule-to-Material-to-Bio Nanoarchitectonics with Biomedical Fullerene Nanoparticles

“…It is no exaggeration to say that it is the science of materials that empowers our modern lifestyle. Currently, the solution to our problems in the energy [ 1 , 2 , 3 , 4 ], environmental [ 5 , 6 , 7 , 8 ], and medical fields [ 9 , 10 , 11 , 12 ] lies in the development of new functional materials. The development of materials is supported by an array of well-established scientific fields.…”