| Summary: | 碩士 === 國立中興大學 === 化學系所 === 102 === In this study, we utilized melamine-formaldehyde resin as carbon and nitrogen precursor, commercial calcium chloride as chemical activation agents and activation at high temperature to prepare nitrogen-containing mesoporous carbon materials. That with high specific surface areas and large pore volumes could be prepared by using the simple and low cost way.
By changing the weight ratio of CaCl2 over melamine-formaldehyde resin(0.5, 1, 2, 4), the temperature of activation (700℃, 800℃, 900℃, 1000℃),and the pH (3, 4, 5) of polymerization as parameters, we discovered that
the amount of the added calcium chloride and the higher of activation temperature does really affect the pore characteristics. At low ratio of activation agents, it produces large amount of micropore and small mesopore (~3-5 nm) with narrow distribution of pore size. At higher ratio,it produces more mesopore and macropore, and it leads more broaden of the pore size distribution. Activation temperature affects activation degree of carbon materials. At lower activation temperature, the carbon materials would be less porosity. It could be decomposed pore structure by higher activation temperature, and this makes lower specific surface areas. The greatest porosity of experimental conditions is MC-2-800-4 with the highest specific surface area 1442 m2g-1 and total pore volume 1.733 cm3g-1.
The pore size distribution of mesoporous makes up by two parts, one is at 3.41nm smaller size and more narrow of distribution, the other is at 25.1nm larger size and more broaden of distribution.
The BET Surface Area and Pore Analyzer is employed in analyzing porosity of carbon materials at all experimental conditions. TEM and SEM are used to observe the morphology of carbon materials under microcosmic
scale. And to understand how the porous arise by references.
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