- 學位論文
從鉻金屬有機骨架加熱製備孔洞性含氧化鉻之碳材
Preparation of porous carbon contained chromium oxide from pyrolysis of chromium metal-organic frameworks
摘要
本論文以鉻金屬有機骨架作為前驅物，加熱製備孔洞性含氧化鉻之碳材。以氯化鉻 (chromium (III) chloride hexahydrate) 作為過渡金屬試劑來源，2-氨基對苯二甲酸 (2-aminoterephthalic acid) 作為有機配位基，藉由水熱合成法，合成鉻金屬有機骨架: MIL-88B-NH2(Cr)。 利用粉末X-射線繞射儀 (PXRD) 初步鑑定化合物的結構；以掃描式電子顯微鏡 (SEM) 觀察晶體的形貌和粒徑大小；熱重分析儀 (TGA)、紫外光-可見光光譜儀 (UV-Vis) 及孔徑分析儀，探討化合物之特性。 以 MIL-88B-NH2(Cr) 作為前驅物，於惰性氣體N2的環境下，分別以高溫500 oC、700 oC、800 oC及900 oC加熱，不同溫度加熱後之產物，分別以500H、700H、800H及900H表示之。於性質鑑定，利用PXRD初步鑑定化合物之結構；SEM觀察晶體之形貌和粒徑大小；EDS作為樣品 表面 之元素 分析 ；TEM觀察顆粒分布之情形；UV -VisVisVis測量分子吸收特性 測量分子吸收特性 測量分子吸收特性 ；孔徑分析儀測量對於氮氣氣體的吸脫附性質與孔洞特性。 實驗結果顯示700H、800H及900H皆形成孔洞性含氧化鉻之碳材，Cr2O3顆粒均勻分布於碳材中，顆粒約小於6.0 nm，其中800H比表面積最高達517.2 m2/g。
並列摘要
In this thesis, porous carbon contained chromium oxide from pyrolysis of chromium metal-organic frameworks has been prepared. The chromium metal-organic framework, MIL-88B-NH2(Cr), has been synthesized by solvothermal reactions of chromium (III) chloride hexahydrate with 2-aminoterephthalic acid (NH2-1,4-BDC). The MIL-88B-NH2(Cr) characterization is investigated by powder X-ray diffraction (PXRD), scanning electron microscopy (SEM), thermogravimetric analysis (TGA), Ultraviolet-Visible Spectrophotometer (UV-Vis) and gas adsorption. Ｂy using the MIL-88B-NH2(Cr) as template, the pyrolysis of MIL-88B-NH2(Cr) was applied with high temperature of 500 oC, 700 oC, 800 oC and 900 oC in an inert gas N2 atmosphere, respectively. All the corresponding samples are called 500H, 700H, 800H and 900H, which have been characterized by PXRD, SEM, EDS, TEM, UV-Vis and gas adsorption. The results show that 700H, 800H and 900H generate the formation of porous carbon contained chromium oxide. The Cr2O3 particles are homogeneous distributed inside the porous carbon material with the particles size about 6.0 nm. Among these samples, the 800H has highest specific surface area with 517.2 m2/g.