碳化與石墨化代表二種無氧狀態下的熱處理溫度，前者約在400-800C而產物主要是sp2-sp3混成的無序碳；後者發生在1600C以上而產物是規則排列的碳層。自從1960年代發現在紫外光的照射下，二氧化鈦具備光裂解有機化合物的能力後，關於光觸媒的原理、機制及相關應用已被廣泛研究。大多數的研究聚焦在二氧化鈦改質以增加效率，較少著墨於二氧化鈦裂解有機化合物後的變化，因此本實驗致力於分析二氧化鈦在有機化合物裂解後於表面形成的碳生成物的結構及元素分析。
本實驗以亞甲基藍為裂解物，以市售二氧化鈦P25進行光裂解、吸附的實驗後，蒐集溶液中的二氧化鈦製成粉末樣品，以電子顯微鏡觀測二氧化鈦表面的變化，並利用拉曼光譜分析裂解亞甲基藍的碳訊號。為了確認碳訊號是由光裂解亞甲基藍所生成，以甲基橙的樣品作為對照組，將樣品經高溫熱處理後再進行電子顯微鏡和拉曼光譜的分析。最後再利用固態核磁共振和化學分析電子能譜分析表面碳生成物的成份，發現透過紫外光催化二氧化鈦裂解亞甲基藍，可以在常溫下於二氧化鈦表面生成sp2的碳層。

Carbonization and graphitization represent O2-free heat treatments at different temperatures; the former lies between 400-800C and products mainly consist of sp2-sp3 hybridized carbon with a low content of π-π conjugated structure and ill-layer orientation. The latter, on the other hand, takes place at a temperature exceeding 1600C so graphitized materials display well organized layer-by-layer structure. TiO2 is considered an ideal and powerful photocatalyst due to its chemical stability, nontoxicity, high reactivity and low cost for large scale of production. This work demonstrates for the first time carbon production at room temperature by TiO2 photo-catalysis of methylene blue (MB). Sp2-based carbon formation on TiO2 surfaces which compromises photocatalysis.

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