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Four kinds of mannitol-based ketal-linked porous organic polymers ( MKPOPs ) were successfully synthesized through condensation reaction between aromatic acetyl monomers and mannitol, catalyzed by p -toluenesulfonic acid. The structure of resulting polymers was confirmed by Fourier transform infrared and solid-state 13 C nuclear magnetic resonance spectrum measurements. The porosities of MKPOPs were investigated by gas adsorption experiments and the results indicate high carbon dioxide uptake (up to 11.5 wt% at 273 K and 1.0 bar) for MKPOPs due to the predominant microporous and hydroxyl-rich structures. Remarkably, MKPOPs exhibit excellent selective adsorption performances for carbon dioxide over methane (9.9–14.2, IAST at 273 K and 1.0 bar). These studies are of significant importance for MKPOPs and their potential application in selective gas adsorption.

Triazine-based porous carbon materials (TPCs) have been synthesized via cyclotrimerization of aromatic tetranitriles and in situ carbonization. The resulting TPCs have high surface area (above 1200 m2 g−1), large pore volume (above 1.4 cm3 g−1), and hierarchical pore structures with micropores (0.63–1.24 nm) and mesopores (2.4–20 nm). Gas adsorption experiments demonstrate their promising hydrogen uptake capacity, up to 2.34 wt% at 77 K and 1.0 bar, due to the hierarchical porosity that facilitates the diffusion and adsorption of gas molecules.

Four acetal-linked porous organic polymers (MAPOP-1–4) have been synthesized by the reaction of multi-aldehyde monomers and mannitol under solvothermal conditions without a template or a metal catalyst. Fourier transform infrared and solid-state 13C cross-polarization/magic-angle-spinning nuclear magnetic resonance spectroscopic measurements were utilized to confirm the structures of the obtained polymers. MAPOPs exhibit high physicochemical stability and a considerable Brunauer–Emmett–Teller specific surface area ranging from 310 to 920 m2 g−1. Owing to their microporous structures, together with their hydroxyl-rich skeletons, MAPOP-1–4 show high carbon dioxide adsorption capability (11.6–13.5 wt% at 273 K and 1.0 bar), heat of adsorption (29.0–31.6 kJ mol−1), and remarkable CO2/CH4 selectivity (8.1–11.6, IAST at 273 K and 1.0 bar). These performances of MAPOP-1–4 make them promising materials in the applications of small gas storage and selective capture.

Carbazole-based oxidative coupling polymerization is an efficient method to prepare various porous polycarbazoles without requirement of any specific functional groups for coupling polymerization. Herein, facile preparation of porous conjugated polymers (CPOP-11 and CPOP-12) using porphyrin or Fe(II)–porphyrin as core structures through this approach is reported. The Brunauer–Emmett–Teller specific surface area of the obtained polymers is up to 1320 m2 g−1, which is comparable to metalloporphyrin based porous polymers prepared by other coupling polymerization methods. It is worth noting that the adsorption amount of toluene by CPOP-12 is high up to 1192 mg g−1 (about 13.0 mmol g−1) at its saturated vapor pressure, which would be very promising to eliminate harmful small aromatic molecules in the environment. As a kind of hydrophobic material, CPOP-11 could be more useful to extract methanol from water due to its high mass ratio of adsorbed methanol to water. Meanwhile, a porous polymer containing Fe(II)–porphyrin (CPOP-12) is also an effective catalyst for the formation of glycosyl sulfoxides from sulfides by promoting the transfer of oxygen atoms and can be reused without significant decrease in catalytic activity and amount of catalyst.

Considering the high reactivity of the C–H bonds in fluorobenzenes for direct arylation and special properties of fluorinated polymers, herein, synthesis of fluorinated porous organic polymers via direct C–H arylation polycondensation is explored. The obtained polymers (FPOP-1 and FPOP-2) are well characterized and show high porosities with Brunauer–Emmett–Teller specific surface area of above 1000 m2 g–1. Different pore size distribution (PSD) profiles of porous polymers can be obtained by selecting different core constructing monomers. FPOP-2 exhibits a relatively narrower PSD with the dominant pore size at about 0.63 nm, which is more suitable for adsorption of small gas molecules (H2, CO2, and CH4) than FPOP-1. As a porous fluorinated hydrophobic material, FPOP-2 possesses high adsorption ability for toluene (976 mg g–1 at saturated vapor pressure and room temperature) due to its high porosities and binding affinities between the guest molecules and the host network. The good sorption capacity of FPOP...

Microporous organic polymers are a relatively new class of materials that show potential applications in various fields such as heterogeneous catalysis, adsorption, separation, and gas storage. The past decade has witnessed the development of microporous materials (i.e., materials containing pores of dimensions less than 2.0 nm) derived wholly from organic components. Several design strategies have emerged to produce organic polymers with permanent microporosity: i) hypercrosslinked polymers, where extensive crosslinking prevents close packing of polymeric chains, ii) polymers of intrinsic microporosity, where polymers are prepared from rigid, contorted structures that cannot pack efficiently, iii) conjugated microporous polymers, in which the inherent rigidity of most conjugated π-systems lends well to the generation of permanent microporosity, iv) covalent organic frameworks, which are crystalline materials formed by reversible condensation of appropriate multifunctional building blocks. On the basis of recent research progress, this paper will introduce the polymers of intrinsic microporosity and conjugated microporous polymers in major, and the other two kinds of polymers are also involved briefly.

A triazine-based porous carbon material (TPC-1) was prepared directly from a fluorinated aromatic nitrile in molten zinc chloride. Trimerization of the nitrile and subsequent defluorination carbonization of the polymeric network result in the formation of TPC-1. The defluorination process is reversible and can etch the polymeric network to release CFn, thereby generating additional porosity and rendering TPC-1 a nitrogen-rich porous material. TPC-1 shows a high BET surface area of 1940 m2 g−1 and contains both micropores and mesopores, which facilitate the diffusion and adsorption of gas molecules. Gas adsorption experiments demonstrate outstanding uptake capacities of TPC-1 for CO2 (4.9 mmol g−1, 273 K and 1.0 bar), CH4 (3.9 mmol g−1, 273 K and 1.0 bar), and H2 (10.1 mmol g−1, 77 K and 1.0 bar). This straightforward synthesis procedure provides an alternative pathway to prepare high-performance porous carbon materials.

We demonstrate the synthesis of two triptycene-based microporous poly(benzimidazole) networks through condensation of triptycene-hexone with dialdehyde in refluxing glacial acetic acid containing ammonium acetate. The benzimidazole-linkage in the resulting polymers is confirmed by Fourier transform infrared and solid-state 13C CP/MAS NMR spectroscopy. The spindle-shaped morphology of the obtained polymers was also observed through scanning electron microscopy. The materials, with Brunauer–Emmet–Teller (BET) specific surface area over 600 m2 g−1, possess a good hydrogen storage capacity (up to 1.57 wt% at 77 K and 1.0 bar) and a high carbon dioxide uptake (up to 14.0 wt% at 273 K and 1.0 bar). These excellent performances would probably make them promising candidates for gas-selective adsorption, heterogeneous catalysis, and proton-exchange membrane fuel cells.

Graphene-Mn3O4 (GMNO) hybrid porous material is prepared by a hydrothermal method and its performance in carbon dioxide adsorption is investigated. In the synthesis of the GMNO materials, MnO(OH)2 colloid obtained by the hydrolysis of Mn2+ in basic solution was using as the precursor of the Mn3O4. After a hydrothermal reaction of the mixture of graphene oxide (GO) and MnO(OH)2, GO was reduced into graphene and the MnO(OH)2 was transformed into Mn3O4 with enhanced crystallization. X-ray diffraction, thermal gravimetric analysis, transmission electron microscopy, infrared spectra and Raman spectroscopy were taken to characterize the hybrid material. The porosity and the carbon dioxide adsorption ability are measured by gas sorption analysis, in which the as-prepared GMNO hybrid materials exhibit a specific surface area ranging from 140 to 680 m2 g−1 and a maximum carbon dioxide capacity of about 11 wt%.