先前的研究指出，石墨烯的化學惰性可以囚禁自由基並觀察自由基反應。我選用di-tert-butyl peroxide (DTBP)、tert-butanol (TBA)以及tert-butyl nitrite (TBN)作為tert-butoxy自由基前驅物，以365 nm LED做光解反應的光源，在超高真空系統中，利用程溫脫附(TPD)以及反射式吸收紅外光譜(RAIRS)即時即地觀測光反應變化與產物。
TBN質譜(m/z 88)以及N=O震動(1620 cm-1)訊號隨照光時間的下降證實了光解反應的進行，照光後加熱過程隨之出現的產物包括；TBA、isobutene、acetone皆低於200 K就生成脫附。而隨著TBN吸附量的增加也會經由radical coupling產生DTBP。有趣的是，比較TBN於Cu (111)上的化學行為，形成的oxametallacycle中間體可以穩定存活至550 K經重組產生TBA與isobutene。沉積在銅上的石墨烯在低溫下提供了另一條自由基反應路徑，此結果暗示積碳不一定視為催化劑之毒化物。反之，反應的選擇性甚至可以被well-defined的石墨烯所調控。

Our previous work found that graphene enables radical species to be trapped and their on-surface chemistry to be revealed. DTBP, TBA and TBN were utilized as the precursors for generating tert-butoxy radicals in conjunction with 365 nm UV light as the light source for the photolysis. Under ultra-high vacuum conditions, utilizing temperature-programmed desorption (TPD) and reflection-absorption infrared spectroscopy (RAIRS) can in situ observe the transformations and products of the photoreaction.
The mass signals (m/z 88) and the vibration mode of N=O (1620 cm-1) were found to decrease upon the illumination, indicating the accessibility of the photolysis reaction. Post-irradiation heating rendered TBA, isobutene and acetone desorption at a temperature as low as 200 K. In addition, by increasing the exposure of TBN on graphene, DTBP was produced via radical coupling. Intriguingly, unlike graphene, TBN on clean Cu (111) would form a stable oxametallacycle intermediate to 550 K, followed by conversion to TBA and isobutene. Well-defined carbon species, such as graphene, should not be treated as catalytic poison material, instead, it provides a new reaction pathway so that the catalyst selectivity might be tuned.

Chapter 1. Introduction 1
1.1 Background information 1
1.2 Research motivation 8
Chapter 2. Experimental Section 10
2.1 Ultrahigh Vacuum System 10
2.2.1 Materials 12
2.2.2 Preparation of graphene 13
2.3 Temperature-programmed desorption spectroscopy (TPD) 15
2.4 Reflection-absorption infrared spectroscopy (RAIRS) 18
2.5 Raman spectroscopy 22
2.6 Density functional theory (DFT) calculations 24
2.7 UV-LED spot light source 25
2.8 Reagents 27
Chapter 3. Results 28
3.1 Thermochemistry and photochemistry of di-tert-butyl peroxide (DTBP) on graphene 28
3.2 Thermochemistry and photochemistry of tert-butanol (TBA) on graphene 35
3.3.1 Photolysis of tert-butyl nitrite (TBN) on graphene 40
3.3.2 Thermolysis of TBN on graphene 44
3.3.3 Photochemistry of TBN on graphene 49
3.4 Thermochemistry and photochemistry of TBN on Cu (111) 59
Chapter 4. Discussion and Conclusions 64
4.1 Discussion 64
4.2 Conclusions 71
Chapter 5. References. 73

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