Design, fabrication and applications of soft and crytalline metal-organic materials

Abstract

Serendipitous formation of many gel-based materials with possibility of versatile applications initiated significant efforts to rationally design molecules with gelation ability to understand the gelation mechanism. Many -conjugated gelators form gels after self-assembly, which involves certain non-covalent interactions between the molecules but the synthesis of -conjugated gelators is challenging to the environment. To overcome these challenges, supramolecular chemistry has gained extensive importance as an alternative approach for designing -conjugated molecules. It is evident that the design and fabrication of low molecular weight (LMW) (M<3000 Da) gels is the best bottom-up approach for the formation of gel materials. LMW gels have non-covalent interactions with low binding strength, which can restrain high amounts of solvents. The mechanical strength of LMW gels is quite different because of the involvement of the weak bonds than polymeric gels (covalent bond) which indicates several advantages such as thermo-reversible nature, hierarchical aggregates structured by the spontaneous organization of small molecules with probability to tailor the gel properties. Introduction of metal ions in gel materials opens the possibility for more diverse structures and versatile applications.To date, the development of BTA and tetrazole based crystalline and soft metal-organic materials are in great demand due to their unique behavior like aggregate induced enhanced emission (AIEE), swelling capacity, and self-healing property. So, these kinds of molecules can be exploited to generate smart materials to apply as materials to biology. This thesis work includes the LMW gelators based on: ✓ Nitrile derivatives of BTA ✓ Tetrazole derivatives ✓ Transition and inner-transition metallogels based on nitrile derivatives of BTA and tetrazole derivativesThe objective of the present work is to design and fabricate LMW based soft and crystalline metal-organic materials which can be explored for a range of applications in various inter-disciplinary areas.