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Al 2 O 3 -C hybrid aerogels were prepared by a one-pot sol-gel method, supercritical n-hexane drying and carbonization using Al(NO 3 ) 3 ·9H 2 O as the Al 2 O 3 source, resorcinol (R) and furfural (F) as carbon precursors, and propylene oxide (PO) as a gelation initiator. The effects of the Al 2 O 3 contents, the R+F concentrations and the PO/Al molar ratios on the porosity of the hybrid aerogels were investigated using a constant R/F molar ratio of 0.5. It was found that the hybrid aerogels are all mesoporous with an average pore size below 20 nm. The crystalline structure of Al 2 O 3 is γ -type, but its diffraction peaks are quite broad. The hybrid aerogels are monolithic when the Al 2 O 3 content is below 5.31 wt% with an R+F concentration of 10 g/100 mL. The mesopore volume and size, BET surface area and external surface area all increase with increasing PO/Al molar ratio under otherwise identical conditions. The volume shrinkage decreases, carbonization yield increases and the density of the hybrid aerogel exhibits a maximum with an Al 2 O 3 content of 4.93 wt%. The size and volume of the mesopores, and the external surface area decrease with the increasing R+F concentration at PO/Al ratios of 5 and 6, but increase with increasing R+F concentration at a PO/Al ratio of 4.

The Giseeler fluidity method was used to investigate the rheological properties of pitch with and without heat treatment from room temperature to 520 °C. Results show that the fluidity has a good repeatability at different temperatures under different heating rates. The fluidity of the raw pitch slowly increases from 253 to 282 °C, then increases exponentially from 282 to 311 °C near the softening temperature, and finally remains unchanged from 311 to 498 °C. This changing pattern of fluidity with temperature has also been found for heat-treated mesophase pitch and can be formulated by the Arrhenius equation, from which the viscous flow activation energy can be obtained. The toluene-insoluble fraction increases from 67.3% to 88.7% with heat-treatment time and the flow activation energy of the treated mesophase pitch in the Newtonian fluid region at low temperature range is between 203.6 and 294 kJ/mol. [New Carbon Materials 2015, 30(2): 176–180]

A series of porous carbons (PCs) was synthesized from nonporous metal-organic coordination polymers (MOCPs), using in-situ polymerized phenol resin as a carbon precursor. The optimized PC has a BET surface area of 2 368 m2/g and an equilibrium CO2 adsorption capacity of 2.9 mmol/g at 300 K and atmospheric pressure. The porous structure of the PCs can be controlled by the formulations of the carbon precursors and gelation/aging time. Meanwhile, the evaporated Zn from the thermal decomposition of the MOCPs acts as an activation agent during carbonization, which eventually improves the microporosity of the PCs. The CO2 equilibrium adsorption capacity increases with increasing Brunauer-Emmett-Teller surface area of the PCs.

A green and efficient method is presented to synthesize 3D hierarchical porous carbon from a metal organic framework (MOF) formed by 1,4-benzenedicarboxylic acid and zinc nitrate hexahydrate using glucose as the carbon precursor. Glucose was infiltrated into the external surface and/or voids of the cubic MOF, then polymerized and carbonized to form porous carbon. In the meantime, MOF was decomposed into ZnO, which was further reduced by carbon (or CO) into Zn that evaporated during carbonization. The morphology and pore characteristics of the products can be adjusted by changing the reaction time. When the synthesized porous carbon was used as the electrode material for electric double layer capacitors, it exhibited a high initial specific capacitance of 175 F·g−1 at 0.6 A·g−1 and a high capacitance retention of 94.2% at 12 A·g−1 in 1 mol/L NEt4BF4/propylene carbonate electrolyte.