@article { ISI:000308310100032, title = {Control of porosity by using isoreticular zeolitic imidazolate frameworks (IRZIFs) as a template for porous carbon synthesis}, journal = {Chemistry-A European Journal}, volume = {18}, number = {36}, year = {2012}, month = {SEP}, pages = {11399-11408}, publisher = {WILEY-V C H VERLAG GMBH}, address = {BOSCHSTRASSE 12, D-69469 WEINHEIM, GERMANY}, abstract = {

Herein, by using isoreticular zeolitic imidazolate frameworks (IRZIFs) as a template, we report the synthesis, morphology, and gas adsorption properties of porous carbon synthesized by a nanocasting method at 1000 degrees C, in which furfuryl alcohol (FA) was used as a carbon source. By using IRZIFs with variable porosity as templates, we could achieve control over the carbon porosity and H-2 and CO2 uptake. The resultant microporous carbon C-70, synthesized by using ZIF-70 as the template, is the most porous (Brunauer-Emmett-Teller (BET) surface area 1510 m(2)g(-1)). Carbon C-68, synthesized by using ZIF-68, has moderate porosity (BET surface area 1311 m(2)g(-1)), and C-69, synthesized by using ZIF-69, has the lowest porosity in this series (BET surface area 1171 m(2)g(-1)). The porous carbons C-70, C-68, and C-69, which have graphitic texture, have promising H2 uptake capacities of 2.37, 2.15, and 1.96 wt\%, respectively, at 77 K and 1 atm. Additionally, C-70, C-68, and C-69 show CO2 uptake capacities of 5.45, 4.98, and 4.54 mmolg(-1), respectively, at 273 K and 1 atm. The gas uptake trends shown by C-70, C-68, and C-69 clearly indicate the dependence of carbon porosity on the host template. Moreover, the as-synthesized carbons C-70, C-68, and C-69 show variable conductivity.

}, keywords = {Carbon, Hydrogen storage, metal-organic frameworks, microporous materials, zinc}, issn = {0947-6539}, doi = {10.1002/chem.201200957}, author = {Pachfule, Pradip and Biswal, Bishnu P. and Banerjee, Rahul} } @article { ISI:000328099400036, title = {Chemically stable multilayered covalent organic nanosheets from covalent organic frameworks via mechanical delamination}, journal = {Journal of the American Chemical Society}, volume = {135}, number = {47}, year = {2013}, month = {NOV}, pages = {17853-17861}, publisher = {AMER CHEMICAL SOC}, address = {1155 16TH ST, NW, WASHINGTON, DC 20036 USA}, abstract = {

A series of five thermally and chemically stable functionalized covalent organic frameworks (COFs), namely, TpPa-NO2, TpPa-F-4, TpBD-(NO2)(2), TpBD-Me-2, and TpBD-(OMe)(2) were synthesized by employing the solvothermal aldehyde-amine Schiff base condensation reaction. In order to complete the series, previously reported TpPa-1, TpPa-2, and TpBD have also been synthesized, and altogether, eight COFs were fully characterized through powder X-ray diffraction (PXRD), Fourier transform IR (FT-IR) spectroscopy, C-13 solid-state NMR spectroscopy, and thermogravimetric analysis. These COFs are crystalline, permanently porous, and stable in boiling water, acid (9 N HCl), and base (3 N NaOH). The. synthesized COFs (all eight) were successfully delaminated using a simple, safe, and environmentally friendly mechanical grinding route to transform into covalent organic nanosheets (CONs) and were well characterized via transmission electron microscopy and atomic force microscopy. Further PXRD and FT-IR analyses confirm that these CONs retain their structural integrity throughout the delamination process and also remain stable in aqueous, acidic, and basic media like the parent COFs. These exfoliated CONs have graphene-like layered morphology (delaminated layers), unlike the COFs from which they were synthesized.

}, issn = {0002-7863}, doi = {10.1021/ja408121p}, author = {Chandra, Suman and Kandambeth, Sharath and Biswal, Bishnu P. and Lukose, Binit and Kunjir, Shrikant M. and Chaudhary, Minakshi V. and BabaRao, Ravichandar and Heine, Thomas and Banerjee, Rahul} } @article { ISI:000330340200002, title = {Crystalline metal-organic frameworks (MOFs): synthesis, structure and function}, journal = {Acta Crystallographica Section B-Structural Science}, volume = {70}, number = {1, SI}, year = {2014}, month = {FEB}, pages = {3-10}, publisher = {WILEY-BLACKWELL}, type = {Article}, address = {111 RIVER ST, HOBOKEN 07030-5774, NJ USA}, abstract = {

Metal-organic frameworks (MOFs) are a class of hybrid network supramolecular solid materials comprised of organized organic linkers and metal cations. They can display enormously high surface areas with tunable pore size and functionality, and can be used as hosts for a range of guest molecules. Since their discovery, MOFs have experienced widespread exploration for their applications in gas storage, drug delivery and sensing. This article covers general and modern synthetic strategies to prepare MOFs, and discusses their structural diversity and properties with respect to application perspectives.

}, issn = {0108-7681}, doi = {10.1107/S2052520613029557}, author = {Dey, Chandan and Kundu, Tanay and Biswal, Bishnu P. and Mallick, Arijit and Banerjee, Rahul} } @article { ISI:000356176200034, title = {Chemical sensing in two dimensional porous covalent organic nanosheets}, journal = {Chemical Science}, volume = {6}, number = {7}, year = {2015}, month = {APR}, pages = {3931-3939}, publisher = {ROYAL SOC CHEMISTRY}, address = {THOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLAND}, abstract = {

Two new imide-based crystalline, porous, and chemically stable covalent organic frameworks (COFs) (TpBDH and TfpBDH) have been successfully synthesized employing solvothermal crystallization route. Furthermore, thin layered covalent organic nanosheets (CONs) were derived from these bulk COFs by the simple liquid phase exfoliation method. These 2D CONs showcase increased luminescence intensity compared to their bulk counterparts (COFs). Notably, TfpBDH-CONs showcase good selectivity and prominent, direct visual detection towards different nitroaromatic analytes over TpBDH-CONs. Quite interestingly, TfpBDH-CONs exhibit a superior {\textquoteleft}{\textquoteleft}turn-on{\textquoteright}{\textquoteright} detection capability for 2,4,6-trinitrophenol (TNP) in the solid state, but conversely, they also show a {\textquoteleft}{\textquoteleft}turn-off{\textquoteright}{\textquoteright} detection in the dispersion state. These findings describe a new approach towards developing an efficient, promising fluorescence chemosensor material for both visual and spectroscopic detection of nitroaromatic compounds with very low [10(-5) (M)] analyte concentrations.

}, issn = {2041-6520}, doi = {10.1039/c5sc00512d}, author = {Das, Gobinda and Biswal, Bishnu P. and Kandambeth, Sharath and Venkatesh, V. and Kaur, Gagandeep and Addicoat, Matthew A. and Heine, Thomas and Verma, Sandeep and Banerjee, Rahul} } @article { ISI:000373163100005, title = {Chemically stable covalent organic framework (COF)-polybenzimidazole hybrid membranes: enhanced gas separation through pore modulation}, journal = {Chemistry-A European Journal}, volume = {22}, number = {14}, year = {2016}, month = {MAR}, pages = {4695-4699}, publisher = {WILEY-V C H VERLAG GMBH}, address = {POSTFACH 101161, 69451 WEINHEIM, GERMANY}, abstract = {

Highly flexible, TpPa-1@PBI-BuI and TpBD@PBI-BuI hybrid membranes based on chemically stable covalent organic frameworks (COFs) could be obtained with the polymer. The loading obtained was substantially higher (50\%) than generally observed with MOFs. These hybrid membranes show an exciting enhancement in permeability (about sevenfold) with appreciable separation factors for CO2/N-2 and CO2/CH4. Further, we found that with COF pore modulation, the gas permeability can be systematically enhanced.

}, keywords = {covalent organic frameworks, Gas separation, membranes, microporous materials, pore modulation}, issn = {0947-6539}, doi = {10.1002/chem.201504836}, author = {Biswal, Bishnu P. and Chaudhari, Harshal D. and Banerjee, Rahul and Kharul, Ulhas K.} } @article {43442, title = {Constructing covalent organic frameworks in water via dynamic covalent bonding}, journal = {Iucrj}, volume = {3}, year = {2016}, month = {NOV}, pages = {402-407}, abstract = {The formation of keto-enamine based crystalline, porous polymers in water is investigated for the first time. Facile access to the Schiff base reaction in water has been exploited to synthesize stable porous structures using the principles of Dynamic Covalent Chemistry (DCC). Most credibly, the water-based Covalent Organic Frameworks (COFs) possess chemical as well as physical properties such as crystallinity, surface area and porosity, which is comparable to their solvothermal counterparts. The formation of COFs in water is further investigated by understanding the nature of the monomers formed using hydroxy and non-hydroxy analogues of the aldehyde. This synthetic route paves a new way to synthesize COFs using a viable, greener route by utilization of the DCC principles in conjunction with the keto-enol tautomerism to synthesize useful, stable and porous COFs in water.}, doi = {10.1107/S2052252516013762}, author = {Thote, Jayshri and Aiyappa, Harshitha Barike and Kumar, Raya Rahul and Kandambeth, Sharath and Biswal, Bishnu P. and Shinde, Digambar Balaji and Roy, Neha Chaki and Banerjee, Rahul} }