Indian Association for the Cultivation of Science

About: Indian Association for the Cultivation of Science is a education organization based out in Kolkata, India. It is known for research contribution in the topics: Catalysis & Excited state. The organization has 3867 authors who have published 10457 publications receiving 220098 citations.

A new strongly paramagnetic cerium-containing microporous MOF for CO2 fixation under ambient conditions.

Abstract: Metal organic frameworks (MOFs) bearing multicarboxylate linkers are in great demand for designing robust heterogeneous catalysts. A new microporous Ce(III)-based metal organic framework (Ce2NDC3) has been synthesized under solvothermal conditions, which showed strong paramagnetism and a CO2 uptake capacity of 1.64 mmol g−1 (7.23 weight%) at 273 K. The Ce2NDC3 showed high catalytic activity in CO2 fixation for the synthesis of cyclic carbonates with a maximum yield of 92% at ambient temperature and pressure. This rare earth metal-based MOF has been well characterized by single crystal X-ray diffraction, PXRD, N2 adsorption/desorption, UHR-TEM, FESEM, FTIR, 13C MAS NMR and TGA. Here, we have carried out magnetic analysis, which revealed that the Ce(III) in this MOF exhibited 2F5/2 magnetism in the ground state. The Ce2NDC3 catalyst showed high recycling efficiency in CO2 fixation reactions, together with retention of the MOF structure after several rounds of reuse. Presumably, the presence of acidic Ce(III) metal ions and microporosity in the coordinated polymer network is responsible for the high catalytic activity.

Amino Acid Based Low-Molecular-Weight Ionogels as Efficient Dye-Adsorbing Agents and Templates for the Synthesis of TiO2 Nanoparticles

Abstract: The gelation of ionic liquids is attracting significant attention because of its large spectrum of applications across different disciplines. These ‘green solvents’ have been the solution to a number of common problems due to their eco-friendly features. To expand their applications, the gelation of ionic liquids has been achieved by using amino acid-based low-molecular-weight compounds. Variation of individual segments in the molecular skeleton of the gelators, which comprise the amino acid and the protecting groups at the N and C termini, led to an understanding of the structure–property correlation of the ionogelation process. An aromatic ring containing amino acid-based molecules protected with a phenyl or cyclohexyl group at the N terminus were efficient in the gelation of ionic liquids. In the case of aliphatic amino acids, gelation was more prominent with a phenyl group as the N-terminal protecting agent. The probable factors responsible for this supramolecular association of the gelators in ionic liquids have been studied with the help of field-emission SEM, 1 H, NMR, FTIR, and luminescence studies. It is the hydrophilic–lipophilic balance that needs to be optimized for a molecule to induce gelation of the green solvents. Interestingly, to maximize the benefits from using these green solvents, these ionogels have been employed as templates for the synthesis of uniform-sized TiO 2 nanoparticles (25–30 nm). Furthermore, as a complement to their applications, ionogels serve as efficient adsorbents of both cationic and anionic dyes and were distinctly better relative to their organogel counterparts.