本研究以蔗糖為碳源材料，經水熱碳化步驟成為初步碳化材料，或是藉由絕氧煅燒提高碳化程度。接著用此含碳材料當作成為活化前驅物，與KOH活化劑混合後進行高溫化學活化，經清洗乾燥後得到高比表面積活性炭。 為了研究影響高比表面積活性炭的氣體吸附現象之成因，我們進行一系列的儀器分析。使用SEM觀察添加氨水後合成的水熱產物之粒子大小和形貌，使用FTIR鑑定材料內部的化學官能基成分，使用粉末XRD鑑定材料的石墨化程度和孔洞結構，最後用恆溫氮氣吸附儀測量比表面積、孔洞結構和常壓氫氣吸附量。 經過上述研究後發現，我們製備的含氮活性炭ACL1A8K4除了具有比表面積3500 m2/g，還有豐富的石墨層狀結構以及大規模的微孔洞結構，是未來在各個領域應用的良好材料。 Activated carbons with high specific surface area were prepared with sucrose as the starting materials. Sucrose was first converted to carbonaceous materials by the hydrothermal carbonization process (175 ℃, 14 hrs), followed by an optional dry carbonization at 450 ℃ (or 600 ℃) in dry nitrogen. The carbonized products were then chemically activated using KOH as the activator. The mixtures of Carbon precursor/KOH at different ratios were heated in dry nitrogen at high temperatures (800 ℃ or 900 ℃). The activation product was then washed with acid to give the final high surface area activated carbon (HSA ACs). A series of analyses was made on the so produced HSA ACs. The particle shapes and sizes of the hydrothermal products were studied by SEM. The surface functional groups were characterized by FTIR analysis. The extent of carbonization and the carbon structure was studied with powder X-ray diffraction (PXRD). The specific surface areas and pore structure was determined from the 77K nitrogen adsorption isotherm. Finally, the possibility of room hydrogen storage was tested by measuring the hydrogen adsorption isotherms below 100 KPa and at room temperature using the volumetric method. In general, the above procedure could produce HAS ACs with BET area above 2000 m2/g. In particular, the addition of ammonia during the hydrothermal carbonization step produced a nitrogen containing activated carbon with BET surface area as high as 3500 m2/g. The sample also exhibits substantial graphite layer structure and wormhole type nanostructures. The hydrogen adsorption isotherms indicate some of our samples were as good as, if not better, than commercial products such as AX-21 and Maxsorb in both BET areas and hydrogen adsorption capacity.
