@article { ISI:000296264700024, title = {Structural and gas adsorption study of a two-dimensional copper-tetrazole based metal-organic framework}, journal = {Current Science}, volume = {101}, number = {7}, year = {2011}, month = {OCT}, pages = {894-899}, publisher = {INDIAN ACAD SCIENCES}, address = {C V RAMAN AVENUE, SADASHIVANAGAR, P B \#8005, BANGALORE 560 080, INDIA}, abstract = {

A new two-dimensional (2D) metal organic framework, Cu-1(4-TBA)(1)(DMBP)(1).DMF (Cu-TBA-3), has been synthesized under solvothermal condition from transition metal cation Cu(II), predesigned ligand 4-(1H-tetrazole-5-yl)benzoic acid (4-TBA) and coligand 4,4{\textquoteright}-dimethy1-2,2{\textquoteright}-bipyridine (DMBP). The structure has been determined by single crystal X-ray crystallography which shows layered 2D structure with square shaped one-dimensional channels. Cu-TBA-3 shows 0.69 wt\% H-2 (at 77 K, 1 atm) and 1.65 mmol/g CO2 (at 298 K, 1 atm) uptake.

}, keywords = {CO2 capture, Hydrogen storage, metal-organic frameworks, microporous materials}, issn = {0011-3891}, author = {Pachfule, Pradip and Banerjee, Rahul} } @article {46326, title = {Ag nanoparticles supported on a resorcinol-phenylenediamine-based covalent organic framework for chemical fixation of CO2}, journal = {Chemistry-An Asian Journal }, year = {2019}, month = {OCT}, type = {Article; Early Access}, abstract = {

Covalent organic frameworks are a new class of crystalline organic polymers possessing a high surface area and ordered pores. Judicious selection of building blocks leads to strategic heteroatom inclusion into the COF structure. Owing to their high surface area, exceptional stability and molecular tunability, COFs are adopted for various potential applications. The heteroatoms lining in the pores of COF favor synergistic host-guest interaction to enhance a targeted property. In this report, we have synthesized a resorcinol-phenylenediamine-based COF which selectively adsorbs CO2 into its micropores (12 angstrom). The heat of adsorption value (32 kJ mol(-1)) obtained from the virial model at zero-loading of CO2 indicates its favorable interaction with the framework. Furthermore, we have anchored small-sized Ag nanoparticles (approximate to 4-5 nm) on the COF and used the composite for chemical fixation of CO2 to alkylidene cyclic carbonates by reacting with propargyl alcohols under ambient conditions. Ag@COF catalyzes the reaction selectively with an excellent yield of 90 \%. Recyclability of the catalyst has been demonstrated up to five consecutive cycles. The post-catalysis characterizations reveal the integrity of the catalyst even after five reaction cycles. This study emphasizes the ability of COF for simultaneous adsorption and chemical fixation of CO2 into corresponding cyclic carbonates.

}, keywords = {CO2 capture, covalent organic frameworks, cyclic carbonates, Propargyl alcohols, silver nanoparticles}, issn = {1861-4728}, doi = {10.1002/asia.201901157}, author = {Chakraborty, Debanjan and Shekhar, Pragalbh and Singh, Himan Dev and Kushwaha, Rinku and Vinod, C. P. and Vaidhyanathan, Ramanathan} } @article {46038, title = {MWCNTs-ZnO-SiO2 mesoporous nano-hybrid materials for CO2 capture}, journal = {Journal of Alloys and Compounds}, volume = {800}, year = {2019}, month = {SEP}, pages = {279-285}, type = {Article}, abstract = {

Carbon nanostructures and metal nanoparticles based nanohybrid materials have been established as one of advantageous materials for various applications. Here, we present hydrothermal and sol-gel process at low temperature for the synthesis of (3-Aminopropyl) triethoxysilane (APTES)-ZnO-multi-walled carbon nanotubes (MWCNTs) mesoporous nanohybrid materials. TEM and XPS measurements show that uniform size and quasi-spherical ZnO nanoparticles were anchored to the surface of the MWCNTs. SEM observation exhibits that the aggregation of ZnO nanoparticles is greatly reduced due to the steric repulsion of grafted organic groups. The maximum CO2 adsorption capacity at 273 K was 1.32 mmol/g for MWCNTs-APTES-ZnO-B nanohybrid. An increase in the density of ZnO nanoparticles on the surface of MWCNTs resulted in a higher affinity towards CO2 at low pressure. This work provides new research directions for making further advances toward practical utilization of MWCNTs-based CO2 adsorbents. (C) 2019 Published by Elsevier B.V.

}, keywords = {CO2 capture, Mesoporous, MWCNTs, Nanohybrid, TEM, XPS}, issn = {0925-8388}, doi = {10.1016/j.jallcom.2019.06.011}, author = {Jena, Kishore K. and Panda, Amulya Prasad and Verma, Savita and Mani, Ganesh Kumar and Swain, S. K. and Alhassan, Saeed M.} } @article {48067, title = {Coordination flexibility aided CO2-specific gating in an iron isonicotinate MOF}, journal = {Chemistry-an Asian Journal}, volume = {17}, year = {2022}, month = {FEB}, pages = {e202101305}, type = {Article}, abstract = {

Coordination flexibility assisted porosity has been introduced into an Iron-isonicotinate metal-organic framework (MOF), (Fe(4-PyC)(2) . (OH). The framework showed CO2-specific gate opening behavior, which gets tuned as a function of temperature and pressure. The MOF {\textquoteleft} s physisorptive porosity towards CO2, CH4, and N-2 was investigated; it adsorbed only CO2 via a gate opening phenomenon. The isonicotinate, representing a borderline soft base, is bound to the hard Fe3+ centre through monodentate carboxylate and pyridyl nitrogen. This moderately weak binding enables isonicotinate to spin like a spindle under the CO2 pressure opening the gate for a sharp increase in CO2 uptake at 333 mmHg (At 298 K, the CO2 uptake increases from 0.70 to 1.57 mmol/g). We investigated the MOF {\textquoteleft} s potential for CO2/N-2 and CO2/CH4 gas separation aided by this gating. IAST model reveals that the CO2/N-2 selectivity jumps from 325 to 3131 when the gate opens, while the CO2/CH4 selectivity increases three times. Interestingly, this Fe-isonicotinate MOF did not follow the trend set by our earlier reported Hard-Soft Gate Control (established for isostructural M2+-isonicotinate MOFs (M=Mg, Mn)). However, we account for this discrepancy using the different oxidation state of metals confirmed by X-ray photoelectron spectroscopy and magnetism.

}, keywords = {CO2 capture, flexible MOF, gating, Isonicotinic}, issn = {1861-4728}, doi = {10.1002/asia.202101305}, author = {Singh, Himan Dev and Nandi, Shyamapada and Chakraborty, Debanjan and Singh, Kirandeep and Vinod, Chathakudath P. and Vaidhyanathan, Ramanathan} } @article {49876, title = {Integrated flue gas CO2 capture and conversion to formate: a sustainable approach}, journal = {ChemSusChem}, volume = {18}, year = {2025}, month = {DEC }, type = {Article}, abstract = {

Industrial CO2 emissions, characterized by dilute streams and impurity complexity, demand energy-efficient mitigation strategies beyond conventional capture technologies. Here, an integrated CO2 capture and conversion (ICCC) system is reported employing a heterogenized iridium catalyst-hydroxyquinoline-ligated Cp*Ir-Cl immobilized on amine-functionalized silica-that directly converts CO2 from synthetic flue gas containing SOx, NOx, and O2 to formate with 100\% selectivity. The catalyst delivers remarkable activity, achieving turnover numbers up to 10,286 within 16 h. Density functional theory reveals that its square pyramidal geometry, induced by the hydroxyquinoline ligand, enhances Ir-N(ring) bond strength and electronic delocalization, thereby improving hydration energy, structural robustness, and catalytic efficiency. Importantly, the catalyst system demonstrates excellent durability, maintaining full activity over five regeneration cycles. Hydrogenation in a 1 M DABCO medium, followed by thermal decomposition of the amine-formate adduct at 150 degrees C, enables efficient lean amine regeneration, allowing subsequent flue gas capture and formate production without performance loss. This closed-loop strategy delivers a sustainable, contaminant-tolerant, and recyclable CO2-to-formate platform with strong promise for scalable industrial deployment.

}, keywords = {CO2 capture, flue gases, integrated capture and conversions, net zero future, Recycle}, issn = {1864-5631}, doi = {10.1002/cssc.202502039}, author = {Kumar, Rohit and Majumder, Supriyo and Singh, Chadrodai Pratap and Samanta, Chanchal and Newalkar, Bharat L. and Krishnamurty, Sailaja and Das, Raj Kumar} }