Microporous organic polymers incorporating dicarboximide units for H 2 storage and remarkable CO 2 capture† Saad Makhseed * a and Jacob Samuel b Anthracene-based microporous polymers comprised of different dicarboximide units (AMPs) are synthesized efficiently by the dioxane forming reactions. AMPs display a BET surface area in the range of 800–1241 m 2 g 1 , and reversibly adsorb 1.90 wt% H 2 at 1.13 bar/77 K with an isosteric heat of adsorption of 7.4 kJ mol 1 . The CO 2 adsorption studies showed an enhanced affinity with a notable uptake capacity reaching more than 4.2 mmol g 1 at 273 K/1 bar combined with a very high isosteric heat value of adsorption (32 kJ mol 1 ). CO 2 adsorption capacity at high pressure is also evaluated reaching up to 15.61 mmol g 1 at 295 K/40 bar for AMP-3. The hydrogen adsorption and impressive CO 2 capture of these materials are attributed to the high concentration of sub-nanometre micropores, as verified by Horvath–Kawazoe (HK) and NLDFT analyses of low-pressure nitrogen adsorption data as well as the benefit of the accessible areas decorated with the imide functionalities within the scaffold of the network polymer. The aforementioned promising results suggest that the incorporation of bismaleimide functional units into the rigid framework structure can improve the performance of AMPs like polymers in gas adsorption applications due to their storage related porous properties. Introduction Microporous materials have always been of great interest due to their property related applications in catalysis, gas storage and gas separation. 1 Despite their high surface area along with the remarkable N 2 uptake capacity and tunable pore sizes, inor- ganic materials (hybrid porous materials) such as metal– organic frameworks (MOFs) usually suffer from low hydro- thermal and physicochemical stabilities. 2 This, in particular, has signicantly increased interest in the development of microporous organic materials which have certain advantages over the former materials, arising from the wide range of architecture diversity through which surface area, micropore size and accessible chemical functionality can be synthetically tuned according to the intended applications in these organic structures. Therefore many approaches have been successfully adapted to develop different classes of microporous organic materials such as polymers of intrinsic microporosity (PIMs), 3 hyper-crosslinked polymers (HCPs), 4 covalent organic frame- works (COFs) 5 and conjugated microporous polymers (CMPs) 6 to overcome the limitations of existing porous materials. Many of the aforementioned polymeric materials demonstrate outstanding properties in terms of chemical nature and porous properties which makes them highly promising candidates for applications in gas storage and separation as has been reported by Ben et al. who described a microporous polyphenylene network (PAF-1) with an unprecedented high surface area of 7100 m 2 g 1 together with high uptake capacities of hydrogen and carbon dioxide. 7 These remarkable sorption characteristics offered by such organic polymers encourage the construction of highly porous materials based on the outcomes of the later achievements and the synthetic diversication of primary building block organic components. Of the organic porous materials, PIM is considered a promising candidate which can be used for a wide range of applications including heterogeneous catalysis, 8 membrane separations 9 and adsorption of organic compounds. 10 The relatively high surface area featuring a greater predominance of ultramicropores (less than 0.7 nm) of such material represents a desirable characteristic for application in gas storage and capture. Therefore, a great deal of efforts has gone towards designing a network polymer with well-dened microporous architecture and chemical composition suitable for the inten- ded applications (i.e. H 2 or CO 2 physisorption). 11,12 This is inspired by the synthetic diversity which offers exible approaches due to the large number of potential monomers that can be obtained to form the PIM material with the specic combination of properties. As a part of this research activity, Neil et al. have recently reported a novel network polymer of a Chemistry Department, Kuwait university, Safat, Kuwait. E-mail: saad.makhseed@ ku.edu.kw; Fax: +965 2481 6482; Tel: +965 24985538 b The Petroleum Research Center, Kuwait Institute for Scientic Research, Ahmadi, Kuwait † Electronic supplementary information (ESI) available. See DOI: 10.1039/c3ta12233f Cite this: J. Mater. Chem. A, 2013, 1, 13004 Received 8th June 2013 Accepted 29th August 2013 DOI: 10.1039/c3ta12233f www.rsc.org/MaterialsA 13004 | J. Mater. Chem. A, 2013, 1, 13004–13010 This journal is ª The Royal Society of Chemistry 2013 Journal of Materials Chemistry A PAPER