@article { ISI:000309370500004, title = {Carbon dioxide capture by metal organic frameworks}, journal = {Indian Journal of Chemistry Section A-Inorganic Bio-Inorganic Physical Theoretical \& Analytical Chemistry}, volume = {51}, number = {9-10, SI}, year = {2012}, month = {SEP}, pages = {1223-1230}, publisher = {NATL INST SCIENCE COMMUNICATION-NISCAIR}, address = {DR K S KRISHNAN MARG, PUSA CAMPUS, NEW DELHI 110 012, INDIA}, abstract = {

The design and synthesis of functionalized metal organic framework materials (MOFs) for reversible physisorption of CO2 is discussed. This strategy of CO2 adsorption in MOFs requires less energy for regeneration than materials relying on chemisorption. As a result the MOFs have received considerable attention as sorbent materials for strategic gases such as CO2 and H,. In this review, we have discussed different MOFs and hybrid materials containing MOFs which can adsorb CO2 at room temperature. In order to achieve high adsorption capacity, fast CO2 adsorption-desorption and low energy requirement for regeneration are necessary. Several avenues for increasing the CO2 adsorption capacity of such materials, for instance, introduction of open metal sites and the use of ligand molecules with specific functionalities (like -OH or -NH2) have been described. It has been observed that CO2 loading capacity of MOFs increases with functionalization. Herein, we have discussed how N-containing and fluorinated MOFs are designed to achieve higher CO2 loading than their non-functionalized counterparts. Nanocarbons (e.g. carbon nanotubes, carbon nanofibres, etc.) are porous materials and a blend of these porous materials with porous MOFs or porous carbon derived from MOFs may act as a better adsorbate than even the pure materials. Enhancement of CO2 loading by nanocarbon-MOF hybrid material is also discussed.

}, keywords = {Carbon dioxide adsorbents, Carbon dioxide capture, hybrid materials, Metal organic frameworks, Nanocarbons, Porous nanocarbons}, issn = {0376-4710}, author = {Saha, Subhadeep and Chandra, Suman and Garai, Bikash and Banerjee, Rahul} } @article { ISI:000328437200053, title = {Hydrolytic conversion of a metal-organic polyhedron into a metal-organic framework}, journal = {Angewandte Chemie-International Edition}, volume = {52}, number = {51}, year = {2013}, month = {DEC}, pages = {13755-13759}, publisher = {WILEY-V C H VERLAG GMBH}, address = {BOSCHSTRASSE 12, D-69469 WEINHEIM, GERMANY}, keywords = {cage compounds, crystal engineering, hydrophobic effect, metal-organic frameworks, Self-assembly}, issn = {1433-7851}, doi = {10.1002/anie.201307486}, author = {Mallick, Arijit and Garai, Bikash and Diaz, David Diaz and Banerjee, Rahul} } @article { ISI:000339090400033, title = {Distinctive PdCl2-mediated transformation of Fe-based metallogels into metal-organic frameworks}, journal = {Crystal Growth \& Design}, volume = {14}, number = {7}, year = {2014}, month = {JUL}, pages = {3434-3437}, publisher = {AMER CHEMICAL SOC}, type = {Article}, address = {1155 16TH ST, NW, WASHINGTON, DC 20036 USA}, abstract = {

Simple, efficient conversion of viable Fe3+-based metallogels into Fe-metal-organic frameworks (MOFs) has been achieved by PdCl2-mediated gel degradation. The metallogels and the resulting MOFs have been characterized, and a probable mechanism for the event has been elucidated.

}, issn = {1528-7483}, doi = {10.1021/cg500368q}, author = {Aiyappa, Harshitha Barike and Saha, Subhadeep and Garai, Bikash and Thote, Jayshri and Kurungot, Sreekumar and Banerjee, Rahul} } @article {46382, title = {Photochromic metal organic frameworks for inkless and erasable printing}, journal = {Acta Crystallographica A-Foundation and Advances}, volume = {70}, year = {2014}, month = {MAY}, pages = {C110}, type = {Meeting Abstract}, keywords = {Erasable Printing, Inkless Printing, metal organic framework}, issn = {2053-2733}, author = {Garai, Bikash and Banerjee, Rahul} } @article { ISI:000360658000003, title = {New imaging reagents for lipid dense regions in live cells and the nucleus in fixed MCF-7 cells}, journal = {Journal of Materials Chemistry B}, volume = {3}, number = {36}, year = {2015}, month = {AUG}, pages = {7177-7185}, publisher = {ROYAL SOC CHEMISTRY}, address = {THOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLAND}, abstract = {

Two new uracil (U) and 5-flurouracil (5-FU) labeled ruthenium(II)-polypyridyl based cellular imaging reagents are reported. Confocal laser scanning microscopic images with live and paraformaldehyde (PFA) fixed MCF-7 cells are examined using these two low-cytotoxic reagents. Experimental results show that these two complexes, appropriately functionalized with U (1) and 5-FU (2), have specific affinity for the lipid dense regions like the endoplasmic reticulum, cell membrane, and cytoplasmic vacuoles in live MCF-7 cells, and dye internalization in these regions happened following an endocytosis pathway. Interestingly, these two complexes are found to be localized in the nucleus of the PFA fixed cells. For fixed cells, presumably the lipid layer disruption helped in the explicit localization of the complexes 1 and 2 in the cell nucleus through specific interaction with cellular DNA. Poor and non-specific internalization of an analogous model complex 3, without having a U or 5-FU moiety, reveals the definite influence of U or 5-FU as well as the role of lipophilicity of the respective complex 1 and 2 in the cellular internalization process. Apart from these, a large Stokes shift (similar to 160 nm) and an appreciably long lived (MLCT)-M-3 excited state (similar to 320 ns) in aq. buffer medium (pH 7.4) are other key features for complexes 1 and 2. Unlike the common nuclear DNA staining reagents like DAPI, these low-cytotoxic reagents are found to be highly stable towards photo-bleaching upon irradiation with 455 nm at the MLCT band for these complexes.

}, issn = {2050-750X}, doi = {10.1039/c5tb01309g}, author = {Ramu, Vadde and Ali, Firoj and Taye, Nandaraj and Garai, Bikash and Alam, Aftab and Chattopadhyay, Samit and Das, Amitava} } @article { ISI:000365205000004, title = {Pore surface engineering in porous, chemically stable covalent organic frameworks for water adsorption}, journal = {Journal of Materials Chemistry A}, volume = {3}, number = {47}, year = {2015}, month = {NOV}, pages = {23664-23669}, publisher = {ROYAL SOC CHEMISTRY}, address = {THOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLAND}, abstract = {

Herein, we have explored the possibility of a class of covalent organic frameworks (COFs) as water adsorbing materials. We have selected, synthesized 12 chemically stable functionalized Schiff base COFs and thoroughly studied their water uptake behaviour. Further, a deep understanding was developed with these COFs towards the effects of condensation pressure of water and hydrophilic/hydrophobic groups present in the COF pores on water absorption capacity and ultimately, their recyclability. Among all reported COFs, TpPa-1 shows the highest water uptake of 30 wt\% (368 cm(3) g(-1); 17 mmol g(-1)) at P/P-0 = 0.3, which is also comparable with the recently reported carbon materials and few well known MOFs. This study also reveals that the overall water uptake of COFs can be tuned systematically based on chemical functionality and pore size in a wider window of relative pressures.

}, issn = {2050-7488}, doi = {10.1039/c5ta07998e}, author = {Biswal, Bishnu P. and Kandambeth, Sharath and Chandra, Suman and Shinde, Digambar Balaji and Bera, Saibal and Karak, Suvendu and Garai, Bikash and Kharul, Ulhas K. and Banerjee, Rahul} } @article { ISI:000348147100072, title = {Solid state organic amine detection in a photochromic porous metal organic framework}, journal = {Chemical Science}, volume = {6}, number = {2}, year = {2015}, month = {DEC}, pages = {1420-1425}, publisher = {ROYAL SOC CHEMISTRY}, address = {THOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLAND}, abstract = {

A new Mg(II) based photochromic porous metal-organic framework (MOF) has been synthesized bearing naphthalenediimide (NDI) chromophoric unit. This MOF (Mg-NDI) shows instant and reversible solvatochromic behavior in presence of solvents with different polarity. Mg-NDI also exhibits fast and reversible photochromism via radical formation. Due to the presence of electron deficient NDI moiety, this MOF exhibits selective organic amine (electron rich) sensing in solid state. The organic amine detection has been confirmed by photoluminescence quenching experiment and visual color change.

}, issn = {2041-6520}, doi = {10.1039/c4sc03224a}, author = {Mallick, Arijit and Garai, Bikash and Addicoat, Matthew A. and Petkov, Petko St. and Heine, Thomas and Banerjee, Rahul} } @article { ISI:000349435000092, title = {Unprecedented ferrocene-quinoline conjugates: facile proton conduction via 1D helical water chains and a selective chemosensor for Zn(II) ions in water}, journal = {RSC Advances}, volume = {5}, number = {20}, year = {2015}, month = {JAN}, pages = {15690-15694}, publisher = {ROYAL SOC CHEMISTRY}, address = {THOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLAND}, abstract = {

Two novel ferrocene-quinoline derivatives 3 (C22H19O2N3Fe) and 4 (C34H28O4N6Fe) have been synthesized and structurally characterized. Compound 3 exhibits good proton conductivity through 1D helical water chains. In addition, both compounds 3 and 4 selectively detect Zn2+ ions in water with a detection limit of 2 ppb through multiple channels.

}, issn = {2046-2069}, doi = {10.1039/c4ra13877e}, author = {Ponniah, Joseph S. and Barik, Subrat Kumar and Borthakur, Rosmita and Thakur, Arunabha and Garai, Bikash and Janaa, Sourita and Ghosh, Sundargopal} } @article {43638, title = {Electrocatalytic water oxidation by a molecular cobalt complex through a high valent cobalt oxo intermediate}, journal = {Chemical Communications}, volume = {52}, year = {2016}, month = {AUG}, pages = {11787-11790}, abstract = {Biuret-modified tetraamidomacrocyclic cobalt complex [Co-III-bTAML]- is shown to catalyze electrochemical water oxidation at basic pH leading to the formation of O-2. Electrochemical and spectroscopic studies indicate a high valent cobalt oxo intermediate isoelectronic to Co-V(O) as the active oxidant. The kinetic isotope effect of 8.63 indicates an atom proton transfer mechanism.}, doi = {10.1039/c6cc05773j}, author = {Das, Debasree and Pattanayak, Santanu and Singh, Kundan K. and Garai, Bikash and Sen Gupta, Sayam} } @article { ISI:000366864700011, title = {Employing carboxylic acids in aryne multicomponent coupling triggered by aziridines/azetidines}, journal = {Organic Chemistry Frontiers}, volume = {3}, number = {1}, year = {2016}, month = {NOV}, pages = {71-76}, publisher = {CHINESE CHEMICAL SOC}, address = {PO BOX 1-18, NANKANG, TAIPEI 115, TAIWAN}, abstract = {

The transition-metal-free aryne multicomponent coupling (MCC) involving carboxylic acids initiated by aziridines/azetidines has been reported. The use of aziridines as nucleophiles afforded N-aryl beta-amino alcohol derivatives and the application of azetidines as nucleophilic triggers furnished N-aryl gamma-amino alcohol derivatives in moderate to good yields. These reactions proceed under mild conditions and result in the formation of a new carbon-nitrogen bond and a new carbon-oxygen bond. The utility of carboxylic acids in aryne MCCs has been demonstrated, and the synthetic potential of phenols as acid surrogates in the present aryne MCCs has been realized.

}, issn = {2052-4129}, doi = {10.1039/c5qo00328h}, author = {Roy, Tony and Bhojgude, Sachin Suresh and Kaicharla, Trinadh and Thangaraj, Manikandan and Garai, Bikash and Biju, Akkattu T.} } @article { ISI:000380864900003, title = {Functionalization and isoreticulation in a series of metal-organic frameworks derived from pyridinecarboxylates}, journal = {Inorganic Chemistry}, volume = {55}, number = {15}, year = {2016}, month = {AUG}, pages = {7200-7205}, publisher = {AMER CHEMICAL SOC}, address = {1155 16TH ST, NW, WASHINGTON, DC 20036 USA}, abstract = {

The partially fluorinated metal-organic frameworks (F-MOFs) have been constructed from 3-fltoro-4-pyridinecarboxylic acid and trans-3-fluoro-4-pyridineacrylic acid linkers using Mn2+, Co2+, and, Cd2+ metals via the solvothetrnal method, which show isostructural isomerism with their nonfluorinated counterparts synthesized using 4-pyridinecarboxylic acid and trans-4-pyridineacrylic acid, respectively. The simultaneous effect of partial fluorination and isoreticulation on structure and H-2 adsorption has been studied systematically in isostructural nonfluorinated and partially fluorinated MOFs, which shows that the increment in the hydrogen uptake properties in F-MOFs is not a universal phenomenon but is rather system-specific and changes from one system to another.

}, issn = {0020-1669}, doi = {10.1021/acs.inorgchem.6b00758}, author = {Pachfule, Pradip and Garai, Bikash and Banerjee, Rahul} } @article { ISI:000369665800035, title = {Mechanochemically synthesized covalent organic framework as a proton-conducting solid electrolyte}, journal = {Journal of Materials Chemistry A}, volume = {4}, number = {7}, year = {2016}, month = {JAN}, pages = {2682-2690}, publisher = {ROYAL SOC CHEMISTRY}, address = {THOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLAND}, abstract = {

Mechanochemistry has become an increasingly important synthetic tool for a waste-free environment. However, the poor quality of the so-derived materials in terms of their crystallinity and porosity has been their major drawback for any practical applications. In this report, we have for the first time successfully leveraged such characteristics to show that the mechanochemically synthesized bipyridine based covalent organic framework (COF) outperforms its conventional solvothermal counterpart as an efficient solid-state electrolyte in PEM fuel cells. Marking the first such attempt in COFs, a Membrane Electrode Assembly (MEA) fabricated using the mechanochemically synthesized COF was observed to inhibit the fuel crossover and build up a stable Open Circuit Voltage (OCV = 0.93 V at 50 degrees C), thereby establishing itself as an effective solid electrolyte material (with a proton conductivity of 1.4 x 10(-2) S cm(-1)), while the solvothermally synthesized COF proved ineffective under similar conditions.

}, issn = {2050-7488}, doi = {10.1039/c5ta10521h}, author = {Shinde, Digambar Balaji and Aiyappa, Harshitha Barike and Bhadra, Mohitosh and Biswal, Bishnu P. and Wadge, Pritish and Kandambeth, Sharath and Garai, Bikash and Kundu, Tanay and Kurungot, Sreekumar and Banerjee, Rahul} } @article { ISI:000371021900071, title = {Photochromic metal-organic frameworks for inkless and erasable printing}, journal = {Chemical Science}, volume = {7}, number = {3}, year = {2016}, month = {DEC}, pages = {2195-2200}, publisher = {ROYAL SOC CHEMISTRY}, address = {THOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLAND}, abstract = {

Inkless and erasable printing is the key solution towards a more sustainable paper industry, in terms of reducing paper wastages and the associated environmental hazards from waste paper processing. However, only a few cases have been reported in the literature where inkless printing has been tested in some practical systems. In an attempt to address this solution, we used photochromic metal-organic frameworks (MOFs) and tested their capability as inkless and erasable printing media. The printing was performed using sunlight as the light source on MOF-coated papers. The resulting printing had good resolution and stability, and was capable of being read both by the human eye and smart electronic devices; furthermore, the paper could be reused for several cycles without any significant loss in intensity. Interestingly, different coloured printing with a similar efficiency was achieved by varying the structure of the MOF.

}, issn = {2041-6520}, doi = {10.1039/c5sc04450b}, author = {Garai, Bikash and Mallick, Arijit and Banerjee, Rahul} } @article {43662, title = {Self-exfoliated metal-organic nanosheets through hydrolytic unfolding of metal-organic polyhedra}, journal = {Chemistry-A European Journal}, volume = {23}, year = {2016}, month = {MAY}, pages = {7361-7366}, chapter = {7361-7366}, abstract = {Few-layers thick metal-organic nanosheets have been synthesized using water-assisted solid-state transformation through a combined top-down and bottom-up approach. The metal-organic polyhedra (MOPs) convert into metal-organic frameworks (MOFs) which subsequently selfexfoliate into few-layered metal-organic nanosheets. These MOP crystals experience a hydrophobicity gradient with the inner surface during contact with water because of the existence of hydrophobic spikes on their outer surface. When the amount of water available for interaction is higher, the resultant layers are not stacked to form bulk materials; instead few-layered nanosheets with high uniformity were obtained in high yield. The phenomenon has resulted high yield production of uniformly distributed layered metal-organic nanosheets from three different MOPs, showing its general adaptability.}, doi = {10.1002/chem.201700848}, author = {Garai, Bikash and Mallick, Arijit and Das, Anuja and Mukherjee, Rabibrata and Banerjee, Rahul} } @article {43549, title = {Electrochemical formation of Fe-V (O) and mechanism of its reaction with water during O-O bond formation}, journal = {Chemistry-A European Journal}, volume = {23 }, year = {2017}, month = {MAR}, pages = {3414-3424}, type = {Journal Article}, abstract = {A detailed electrochemical investigation of a series of iron complexes (biuret-modified tetraamido iron macrocycles FeIII-bTAML), including the first electrochemical generation of Fe-V(O), and demonstration of their efficacy as homogeneous catalysts for electrochemical water oxidation (WO) in aqueous medium are reported. Spectroelectrochemical and mass spectral studies indicated FeV(O) as the active oxidant, formed due to two redox transitions, which were assigned as Fe-IV(O)/Fe-III(OH2)and Fe-V(O)/Fe-IV(O). The spectral properties of both of these high-valent iron oxo species perfectly match those of their chemically synthesised versions, which were thoroughly characterised by several spectroscopic techniques. The O-O bond-formation step occurs by nucleophilic attack of H2O on FeV(O). A kinetic isotope effect of 3.2 indicates an atom-proton transfer (APT) mechanism. The reaction of chemically synthesised Fe-V(O) in CH3CN and water was directly probed by electrochemistry and was found to be first-order in water. The pK(a) value of the buffer base plays a critical role in the rate-determining step by increasing the reaction rate several-fold. The electronic effect on redox potential, WO rates, and onset overpotential was studied by employing a series of iron complexes. The catalytic activity was enhanced by the presence of electron-withdrawing groups on the bTAML framework. Changing the substituents from OMe to NO2 resulted in an eightfold increase in reaction rate, while the overpotential increased threefold.}, doi = {10.1002/chem.201605061}, author = {Pattanayak, Santanu and Chowdhury, Debarati Roy and Garai, Bikash and Singh, Kundan K. and Paul, Amit and Dhar, Basab B. and Sen Gupta, Sayam} }