新型炭材料
新型炭材料
신형탄재료
NEW CARBON MATERIALS
2010年
6期
431-437
,共7页
杨永珍%刘旭光%罗秋苹%金琳%许并社
楊永珍%劉旭光%囉鞦蘋%金琳%許併社
양영진%류욱광%라추평%금림%허병사
炭微球%氧化%中空炭微球%形成机理
炭微毬%氧化%中空炭微毬%形成機理
탄미구%양화%중공탄미구%형성궤리
Carbon microspheres%Oxidation%Hollow carbon microspheres%Formation mechanism
采用简单的空气氧化法由实心炭微球制备中空结构的炭微球.通过场发射扫描电子显微镜、高分辨透射电子显微镜、X-射线衍射仪、拉曼光谱和热重分析仪对产物的形貌和结构进行表征.结果表明:中空炭微球的石墨化程度较低.在炭微球的空气热氧化过程中,反应温度对炭微球从实心到中空的结构演变起着关键性的作用,温度越高,中空炭微球的内径越大、壁越薄.其形成机理可认为是炭微球的曲率和结晶度协同作用的结果.亦即,实心炭微球进行热氧化时,其内部的大曲率和低结晶度更易氧化,以致形成中空炭微球.
採用簡單的空氣氧化法由實心炭微毬製備中空結構的炭微毬.通過場髮射掃描電子顯微鏡、高分辨透射電子顯微鏡、X-射線衍射儀、拉曼光譜和熱重分析儀對產物的形貌和結構進行錶徵.結果錶明:中空炭微毬的石墨化程度較低.在炭微毬的空氣熱氧化過程中,反應溫度對炭微毬從實心到中空的結構縯變起著關鍵性的作用,溫度越高,中空炭微毬的內徑越大、壁越薄.其形成機理可認為是炭微毬的麯率和結晶度協同作用的結果.亦即,實心炭微毬進行熱氧化時,其內部的大麯率和低結晶度更易氧化,以緻形成中空炭微毬.
채용간단적공기양화법유실심탄미구제비중공결구적탄미구.통과장발사소묘전자현미경、고분변투사전자현미경、X-사선연사의、랍만광보화열중분석의대산물적형모화결구진행표정.결과표명:중공탄미구적석묵화정도교저.재탄미구적공기열양화과정중,반응온도대탄미구종실심도중공적결구연변기착관건성적작용,온도월고,중공탄미구적내경월대、벽월박.기형성궤리가인위시탄미구적곡솔화결정도협동작용적결과.역즉,실심탄미구진행열양화시,기내부적대곡솔화저결정도경역양화,이치형성중공탄미구.
Hollow carbon microspheres, several micrometers in diameter, were prepared from solid carbon microspheres by a simple oxidation-in-air process. The morphology and structure of these products were characterized by field-emission scanning electron microscopy, high-resolution transmission electron microscopy, X-ray diffraction, Raman spectroscopy, and thermogravimetry. Results indicate that heat treatment temperature in air plays a key role in the evolution of the cavity size and wall thickness of the hollow carbon microspheres with poor graphitization, and high heating temperature leads to a thin wall thickness and large inner diameter. A proposed formation mechanism reveals that the hollow carbon microspheres are formed as a result of the effect of curvature and crystallinity, i.e. the inner part of solid carbon microspheres has a large curvature and a low crystallinity, which is much more easily oxidized to form hollow carbon microspheres when subjected to air oxidation.