Covalent Organic Framework Supported Nanoparticles as Light Weight Nanomagnet
Abstract
Covalent Organic Frameworks (COFs) are a new class of crystalline organic polymers with modular structure & ordered pores. They are cross-linked polymers typically constructed from small building units rich in aromatic groups. They order by pi-pi stacking; thereby producing a high degree of crystallinity. Synthetic accessibility of a library of amine & aldehyde functionalized small molecules has resulted in the easy development of Schiff bond-based COFs. The central feature of this material is an inherent porosity (micro and/or mesoporous) & high surface area. The objective is to develop COFs as supports for nanoparticles (nPs) of transition/lanthanide metal based magnets. Such composites would be employed as light weight nanomagnets (nMs). High surface areas of these COFs make them ideal matrix for dispersing & stabilizing nPs in small sizes sans capping agents. The highly ordered porous structure of these COFs can assemble these magnetic nPs into an ordered array & provide means to control the intrinsic magnetic properties of the nMs. Even with small nM loadings, the complete magnetic character is throughout the material. The COFs can be constructed with a high degree of conjugation and electronic activity--they would become conducting polymers, which interact electronically with metal compounds. Such synergistic interactions will enable modifying the local magnetic character at the COF-nM interfaces. These nM/COF composites have morphologies resembling graphenes that can be integrated into flexible substrates such as paper, textile, polymers, which find use in devices with credit card like shapes and sizes. Such super-composites are meta-materials that can provide means to controlling the spin correlations between the individual magnetic clusters trapped in the COF nanopores.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Jun 11, 2018
- Source ID
- FA23861810121
Entities
People
- Ramanthan Vaidhyanathan
Organizations
- Air Force Office of Scientific Research
- Indian Institutes of Science Education and Research
- United States Air Force