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We report a facile method for the fabrication of three-dimensional (3D) porous materials via the interaction between graphene oxide (GO) sheets and polyethylenimine (PEI) with high amine density at room temperature under atmospheric pressure without stirring. The structural and physical properties of GO-PEI porous materials (GEPMs) are investigated by scanning electron microscopy, X-ray diffraction, thermogravimetric analysis, and nitrogen adsorption-desorption measurement and their chemical properties are analyzed by X-ray photoelectron spectroscopy, infrared spectroscopy, and Raman spectroscopy. GEPMs possess low density and hierarchical morphology with large specific surface area, and big pore volume. Furthermore, the as-prepared 3D porous materials show an excellent adsorption capacity for acidic dyes on the basis of the pore-rich and amine-rich graphene structure. GEPMs exhibit an extremely high adsorption capacity for amaranth (800 mg g(-1)), which are superior to other carbon materials. In addition, GEPMs also exhibit good adsorption capacity for carbon dioxide (11.2 wt % at 1.0 bar and 273 K).

Nitrogen-doped graphene has been demonstrated to be an excellent multifunctional material due to its intriguing features such as outstanding electrocatalytic activity, high electrical conductivity, and good chemical stability as well as wettability. However, synthesizing the nitrogen-doped graphene with a high nitrogen content and large specific surface area is still a challenge. In this study, we prepared a nitrogen-doped graphene aerogel (NGA) with high porosity by means of a simple hydrothermal reaction, in which graphene oxide and ammonia are adopted as carbon and nitrogen source, respectively. The microstructure, morphology, porous properties, and chemical composition of NGA were well-disclosed by a variety of characterization methods, such as scanning electron microscopy, nitrogen adsorption-desorption measurements, X-ray photoelectron spectroscopy, and Raman spectroscopy. The as-made NGA displays a large Brunauer-Emmett-Teller specific surface area (830 m(2) g(-1)), high nitrogen content (8.4 atom %), and excellent electrical conductivity and wettability. On the basis of these features, the as-made NGA shows superior capacitive behavior (223 F g(-1) at 0.2 A g(-1)) and long-term cycling performance in 1.0 mol L(-1) H2SO4 electrolyte. Furthermore, the NGA also possesses a high carbon dioxide uptake capacity at 1.0 bar and 273 K (11.3 wt %).

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We report a facile and scalable method for the preparation of a carbon-based porous material through steam activation of a graphene aerogel (GA). The morphology and porous attributes of the steam activated graphene aerogel (SAGA) have been well investigated by scanning electron microscopy, transmission electron microscopy, and nitrogen adsorption-desorption experiments. The structure and chemical composition of the obtained SAGA have been disclosed through X-ray diffraction, X-ray photoelectron spectroscopy, and Raman spectroscopy. The as-prepared SAGA exhibits a high BrunauerEmmett-Teller specific surface area (830-1230 m 2 g À1 ), an abundant large pore volume (2.2-3.6 cm 3 g À1 ), and excellent thermal stability. The SAGA shows excellent adsorption capabilities for toluene (710 mg g À1 ) and methanol (641 mg g À1 ) at saturated vapor pressure and room temperature.

Hypercrosslinked carbazole-based porous organic polymers were prepared via FeCl3-promoted one-step oxidative coupling reaction and Friedel–Crafts alkylation in one pot.