本研究製備一種奈米金顆粒/發泡石墨烯的結構並用於氨氣感測器的應用。以發泡鎳作為基板，用化學氣相沉積法成長石墨烯於其上，石墨烯的層數為5-10層，利用鹽酸蝕刻將鎳完全去除，即可得到一個三維網狀結構的發泡石墨烯。將其貼附於PET之上以穩固其結構作為基材，並利用濺鍍法將奈米金顆粒沉積於石墨烯表面以進行改質，在本實驗中，亦利用不同的濺鍍參數控制奈米金顆粒的大小。
結果顯示，藉由將奈米金沉積於發泡石墨烯上可明顯增加其在氨氣感測方面的敏感度、響應時間、回復時間等性質。而其感測表現亦隨著沉積奈米金顆粒的大小不同而改變，由於小顆粒之奈米金可以使發泡石墨烯之比表面積大幅度增加，因此其感測表現較大顆粒之奈米金更佳，此外此元件製備簡單可於室溫下對ppm等級濃度氨氣具有高敏感度並具有可逆性。
本研究亦探討不同溫度下此元件對氨氣感測的能力，於高溫環境下元件對氨氣的吸附及脫附能力有明顯的提升，可利用升溫的方式使氣體完全的脫附。

This study used a gold-nanoparticle-decorated graphene foam composite as a sensor for detecting low concentration ammonia gas. Few-layer graphene was grown on the nickel foam by CVD. Then the nickel foam was removed by a etching process to fabricate a three-dimensional graphene foam structure. Graphene foam was then adhered to a PET film to prevent the graphene foam structure from collapse during handling. Gold nanoparticles with different sizes were deposited on the surface of the graphene foam by sputtering. The results showed that the sensitivity, recovery time, and response time of the sensor were enhanced attributing to the deposition of gold nanoparticles on the surface of graphene foam. Size effects of gold nanoparticles on the performance of the sensor were studied and it was found that smaller gold nanoparticles enhance the sensitivity of the device significantly due to the increase of the specific surface area. In addition, the sensor possessing high sensitivity in the range of 50 to 1000 ppm for NH3 and having reversible behavior were detected. The dependence of the sensing ability in the operating temperature was also investigated. In high operating temperature, the ability of adsorption and desorption of the ammonia molecules was remarkable enhanced owing to the fully desorption of the NH3 at elevated temperature.

目錄
摘要 Ⅰ
abstract Ⅱ
致謝 Ⅲ
目錄 Ⅳ
表目錄 Ⅶ
圖目錄 Ⅷ
第一章研究動機 1
第二章文獻回顧 2
2.1 奈米顆粒 2
2.1.1 奈米顆粒的性質 2
2.1.2奈米顆粒的應用 4
2.1.3奈米複合材料 4
2.2碳材料及其衍生應用 5
2.2.1 奈米碳管 6
2.2.2 石墨烯 7
2.3 氣體感測器 10
2.3.1 石墨烯氣體感測器 12
2.3.2 石墨烯氣體感測器的改質 14
第三章實驗步驟及儀器 25
3.1 實驗藥品及材料 25
3.1.1 發泡鎳 25
3.1.2發泡石墨烯之成長 25
3.1.3發泡石墨烯之蝕刻及貼附 27
3.1.4試片製作 28
3.2氣體感測量測基準 28
3.2.1 氣體敏感性 28
3.2.2 響應及回復時間 29
3.3 實驗及試片分析工具 29
3.3.1高溫爐管系統 30
3.3.2電磁加熱攪拌器 30
3.3.3超音波震盪器 30
3.3.4直流式真空濺鍍機 31
3.3.5 拉曼光譜分析 31
3.3.6場發射掃描式電子顯微鏡 32
3.3.7場發射高解析穿透式電子顯微鏡 33
3.3.8霍爾量測器 33
3.3.9化學分析電子能譜儀 34
3.4氣體感測量測系統 34
3.4.1氣體感測量測系統架構 34
3.4.2氨氣濃度計算 35
3.4.3氣體感測操作流程 35
第四章結果與討論 46
4.1 原材料定性分析 47
4.1.1 SEM分析 47
4.1.2 TEM/HRTEM分析 48
4.1.3 EDS分析 48
4.1.4 Raman分析 49
4.1.5 霍爾電性量測 50
4.1.6 XPS分析 50
4.2 氨氣氣體感測 51
4.2.1 室溫下對定量氨氣氣體之電性量測 51
4.2.2 室溫下對不同濃度氨氣氣體之電性量測 52
4.2.3 發泡石墨烯/奈米金顆粒於不同溫度下之氨氣氣體電性量測 53
4.2.4 氣體選擇性 53
4.3 氨氣感測機制 54
第五章結論 70
參考文獻 72

表目錄
表2-1 奈米顆粒性質與應用 16
表2-2 不同方法製造石墨烯之優缺點 17
表2-3 氣體感測器的種類及優缺點比較[35] 18

圖目錄
圖2-1複合材料示意圖[6] 19
圖2-2 (a)石墨(b)鑽石(c)傅勒烯(d)奈米碳管(e)石墨烯的原子結構[9] 19
圖2-3石墨烯在金屬表面析出成長機制示意圖[29] 20
圖2-4石墨烯於鎳基板以不同降溫速率成長之拉曼光譜圖[29] 20
圖2-5 化學參雜對單層石墨烯敏感度的影響[40] 21
圖2-6 還原氧化石墨烯在1%氨氣環境下之電性圖[43] 21
圖2-7 多晶石墨烯之AFM及拉曼光譜比較圖[47] 22
圖2-8 (a)石墨烯、多晶石墨烯、皺摺石墨烯對甲苯(b)石墨烯、多晶石墨烯、皺摺石墨烯對鄰二氯苯之氣體響應圖[47] 22
圖2-9氧化鋅奈米線/石墨烯/金屬複合材料製成圖[48] 23
圖2-10氧化鋅奈米線/石墨烯/金屬複合材料對乙醇氣體感測響應圖 23
圖2-11 石墨烯/奈米金顆粒對氨氣感測響應圖(a)未添加奈米金顆
(b)添加奈米金顆粒[50] 24
圖3-1 發泡石墨烯與成長前後比較圖 37
圖3-2發泡石墨烯/奈米金顆粒元件製作流程圖 38
圖3-3 高溫爐管系統 39
圖3-4電磁加熱攪拌器 39
圖3-5超音波震盪器 40
圖3-6 直流式真空濺鍍機 40
圖3-7 微拉曼光譜儀 41
圖3-8 熱場發掃描式電子顯微鏡 41
圖3-9 鍍金機 42
圖3-10穿透式電子顯微鏡 42
圖3-11 霍爾量測器 43
圖3-12 化學分析電子能譜儀................................43
圖3-13 Keithley電源電錶 44
圖3-14 氣體感測量測系統 44
圖3-15 氣體感測量測系統示意圖 45
圖4-1 發泡鎳之SEM圖 .56
圖4-2 發泡石墨烯之SEM圖 56
圖4-3 不同參數漸鍍奈密金顆粒SEM圖(a)30瓦4秒(b)20瓦5秒(c)10瓦5秒 57
圖4-4 (a)發泡石墨烯之TEM圖(b)發泡石墨烯之HRTEM圖 58
圖4-5 EDS元素分析圖(a)發泡石墨烯(b)奈米金顆粒/發泡石墨烯 59
圖4-6 發泡石墨烯之拉曼光譜分析圖 60
圖4-7鍍金前後之發泡石墨烯拉曼比較圖 60
圖4-8 C 1s之XPS鍵結能圖.................................61
圖4-9 Au 4f之XPS鍵結能圖................................61
圖4-10室溫下對1000 ppm氨氣進行三個循環敏感度改變圖(a)發泡石墨烯(b)11 nm金顆粒/發泡石墨烯(c)9 nm金顆粒/發泡石墨烯(d)7 nm金顆粒/發泡石墨烯 .62
圖4-11 不同試片於1000 ppm下氨氣多循環敏感度比較圖 63
圖4-12室溫下於不同濃度氨氣(1000、500、200、100、50 ppm)環境下之敏感度改變圖(a)發泡石墨烯(b)11 nm金顆粒/發泡石墨烯(c)9 nm金顆粒/發泡石墨烯(d)7 nm金顆粒/發泡石墨烯 64
圖4-13室溫下不同試片於不同濃度(1000、500、200、100、50 ppm)下氨氣敏感度比較圖 65
圖4-14 7 nm奈米金顆粒/發泡石墨烯於不同溫度下分別於1000、500、200、100、50 ppm之氨氣濃度敏感度改變圖(a)室溫、(b)60℃、(c)80℃ 67
圖4-15 7 nm奈米金顆粒/發泡石墨烯於不同溫度下於100 ppm之氨氣濃度敏感度改變比較圖 67
圖4-16 7 nm奈米金顆粒/發泡石墨烯對不同種類氣體敏感度改變比較圖 68
圖4-17 理論金/石墨烯接面能帶結構圖[50] 69

參考文獻

[1] 王世敏,“奈米材料的原理及製備”, 五南出版社,緒論, (2004).
[2] C. Suryanarayana, “Nanocrystalline materials”, International Materials Reviews, Vol.40, pp.41-62, (1995).
[3] C. Suryanarayana and C. C. Koch, “Nanocrystalline materials-Current research and future directions”, Hyper fine Interactions, Vol.130, pp.5-44, (2000). [4] 賴炤銘, 李錫隆, “奈米材料的特殊效應與應用”, The Chinese Chemical Society in Taipei, Vol.61, pp.585-597, (2003).
[5] S. Peng, Y. M. Lee, C. Wang, H. F. Yin and S. Daiand, S. H. Sun, “A Facile Synthesis of Monodisperse Au Nanoparticles and Their Catalysis of CO Oxidation”, Nano Res., Vol.1, pp.229-234, (2008).
[6] B. Harris, “Composite materials”, The Institute of Materials, Britain London, Chapter I, (1999).
[7] Z. P. Chen, W. Ren, L. Gao, B. Liu, S. Pei and H. M. Cheng, “Three-dimensional flexible and conductive interconnected graphene networks grown by chemical vapour deposition”, Nature materials, Vol.10, pp.424-428, (2011).
[8] D. D. L. Chung, “Composite material science and applications functional materials for modern technologies”, Springer-Verlag, Germany Berlin, Chapter I, (2003).
[9] M. Scarselli, P. Castrucci and M. D. Crescenzi, “Electronic and optoelectronic nano-devices based on carbon nanotubes”, Journal of Physics: Condensed Matter, Vol.24, pp.313202-313227, (2012).
[10] E. W. Hill, A. Vijayaragahvan and K. Novoselov, ”Graphene Sensors”, IEEE Sensors Journal, Vol.11, pp.3161-3170, (2011).
[11] H. W. Kro, J. R. Heath, S. C. O’Brien, R. F. Curl and R. E. Smalley, “C60:buckminsterfullerence”, Nature, Vol.318, pp. 162-163, (1985).
[12] S. Iijima, “Helical microtubules of graphitic carbon”, Nature, Vol.354, pp.56-58, (1991).
[13] S. Iijima, “Single-shell carbon nanotube of 1 nm diameter”, Nature, Vol.363, pp.603-605, (1993).
[14] D. S. Bethune, C. H. Kiang and M. S. Devries, “Cobalt catalyzed growth of carbon nanotubes with single atomic layer walls”, Nature, Vol.363 , pp.605–607, (1993).
[15] P. J. F. Harries, ”Carbon nanotubes and related structures :new materials for twenty first century”, Cambridge University Press, Britain Cambridge, (1995).
[16] B. Q. Wei, R. Vajtai and P. M. Ajayan, “Reliability and current carrying capacity of carbon nanotubes”, Applied Physics Letters, Vol.79, pp.1172-1174, (2001).
[17] Z. Yao, C. L. Kane and C. Dekker, “High field electrical transport in single wall carbon nanotubes”, Physical Review Letters, Vol.84, pp.2941-2944, (1999).
[18]D. R. Kauffman and A. Star, “Carbon nanotube gas and vapor sensors”, Angew. Chem. Int. Ed., Vol.47, pp.6550–6570, (2008).
[19] K. S. Novoselov, A. K. Geim, S. V. Morozov, D. Jiang, Y. Zhang, S. V. Dubonos, I. V. Grigorieva and et al., “Electric field effect in atomically thin carbon films”, Science, Vol. 306, pp.666-669, (2004).
[20] C. Lee, X. Wei, J. W. Kysar and J. Hone, “Measurement of the elastic properties and intrinsic strength of monolayer graphene”, Science, Vol.321, pp.385-388, (2008).
[21] I. W. Frank, D. M. Tanenbaum, A. M. van der Zande and P. L. McEuen, “Mechanical properties of suspended graphene sheets”, Journal of Vacuum Science & Technology B: Microelectronics and Nanometer Structure, Vol.25, pp. 2558-2561, (2007).
[22] R. R. Nair, “Fine structure constant defines visual transparency of graphene”, Science, Vol.320, p.1308, (2008).
[23] A. A. Balandin, S. Ghosh, W. Bao, I. Calizo, D. Teweldebrhan, F. Miao and et al., “Superior thermal conductivity of single layer graphene”, Nano Letters, Vol.8, pp.902-907, (2008).
[24] F. Yavari, Z. P. Chen, A. V. Thomas, W. Ren, H. M. Cheng and N. Koratkar, “High sensitivity gas detection using macroscopic three–dimensional graphene foam network”, Scientific Reports, Vol.1, pp.166-200, (2011).
[25] M. J. Allen, V. C. Tung and R. B. Kaner, “Honeycomb carbon: a review of graphene”, Chemical Reviews, Vol.110, p.132-145, (2010).
[26] K. S. Novoselov, A. K. Geim, S. V. Morozov, D. Jiang, Y. Zhang, S. V. Dubonos and et al., “Electric field effect in atomically thin carbon films”, Science, Vol.306, pp.666-669, (2004).
[27] J. Wintterlina and M. L. Bocquet, “Graphene on metal surfaces”, Surface Science, Vol.603, pp.1841-1852, (2009).
[28] X. Li, W. Cai, L. Colomboand and R. S. Ruoff, “Evolution of graphene growth on Ni and Cu by carbon isotope labeling”, Nano Letter, Vol.9, pp.4268-4272, (2009).
[29] Q. Yu, J. Lian, S. Siriponglert, H. Li, Y. P. Chenand and S. S. Pei, “Graphene segregated on Ni surface and transferred to insulators”, Applied Physics Letters, Vol.93, pp.1-3, (2008).
[30] A. Reina, S. Thiele, X. Jia and S. Bhaviripudi, “Growth of large area single and bi-layer graphene by controlled carbon precipitation on polycrystalline Ni surfaces”, Nano Research, Vol.2, pp.509-516, (2009).
[31] X. Li, C. W. Magnuson and A. Venugopal, “Graphene films with large domain size by a two-step chemical vapor deposition process”, Nano Letter, Vol.10, pp.4328-4334, (2010).
[32] W. S. Hummers Jr. and R. E. Offeman, “Preparation of graphitic oxide”, Journal of the American Chemical Society, Vol.80, p.1339, (1958).
[33] P. Zhu, M. Shen, S. Xiao and D. Zhang, “Experimental study on there ducibility of graphene oxide by hydrazine hydrate”, Journal of Physics: Condensed Matter, Vol.406, pp.498-502, (2011).
[34] X. Li, G. Zhang, X. Bai, X. Sun, X. Wang, E. Wang and et al., “Highly conducting graphene sheet and Langmuir-Blodgett films”, Nature Nanotechnology, Vol.3, pp.538-542, (2008).
[35] X. Liu, S. Cheng, H. Liu, S. Hu, D. Zhang and H. Ning, “A survey on gas sensing technology”, Sensors, Vol.12, pp.9635-9665, (2012).
[36] S. M. Kanan, O. M. El-Kadri, I. A. Abu-Yousef and M. C. Kanan, ”Semiconducting Metal oxide based sensors for selective gas pollutant detection”, Sensors, Vol.9, pp.8158-8196, (2009).
[37] M. Batzill and U. Diebold, “The surface and materials science of tin oxide”, Progress in Surface Science, Vol.79, pp.47-154, (2005).
[38] T. Zhang, S. Mubeen, N. V. Myung and M. A. Deshusses, “Recent progress in carbon nanotube based gas sensors”, Nanotechnology, Vol.19, pp.332001-332014, (2008).
[39] R. Leghrib, E. Llobet, A. Felten, J. J. Pireaux, Z. Zanolli, J. C. Charlier and et al.,“NO2 and CO interaction with plasma treated Au-decorated MWCNTs: Detection pathways”, Procedia Chemistry, Vol.1, pp.931-934, (2009).
[40] F. Schedin, A. K. Geim, S. V. Morozov, E. W. Hill, P. Blake, M. I. Katsnelson and et al., “Detection of individual gas molecules adsorbed on graphene”, Nature materials, Vol.6, pp.652-655, (2007).
[41] W. Yuan and G. Shi, ”Graphene-based gas sensors”, Journal of Materials Chemistry A, Vol.1, pp.10078-10091, (2013).
[42] M. Gautam and A. H. Jayatissa, “Gas sensing properties of graphene synthesized by chemical vapor deposition”, Materials Science and Engineering C, Vol.31, pp.1405-1411, (2011).
[43] G. Lu, L. E. Ocola and J. Chen, “Reduced graphene oxide for room temperature gas sensors”, Nanotechnology, Vol.20, pp. 445502-445511, (2009).
[44] R. K. Joshi, H. Gomez, F. Alvi and A. Kumar, “Graphene films and ribbons for sensing of O2, and 100 ppm of CO and NO2 in Practical Conditions”, Journal of Physical Chemistry C, Vol.114, pp.6610-6613, (2010).
[45] W. Wu, Z. Liu, L. A. Jauregui, Q. Yua, R. Pillai, H. Caoc and et al., “Wafer scale synthesis of graphene by chemical vapor deposition and its application in hydrogen sensing”, Sensors and Actuators B, Vol.150, pp.296-300, (2010).
[46] Y. H. Zhang, Y. B. Chen, K. G. Zhou, C. H. Liu, J. Zeng, H. L. Zhang and et al., “Improving gas sensing properties of graphene by introducing dopants and defects: a first principles study”, Nanotechnology, Vol.20, pp.1885504-1885511, (2009).
[47] A. S. Khojin, D. Estrada, K. Y. Lin, M. H. Bae, F. Xiong, E. Pop and et al., “Polycrystalline graphene ribbons as chemiresistors”, Advanced Materials, Vol.24, pp.53-57, (2012).
[48] J. Yi, J. M. Lee and W. I. Park, “Vertically aligned ZnO nanorods and graphene hybrid architectures for high sensitive flexible gas sensors”, Sensors and Actuators B, Vol.155, pp.264-269, (2011).
[49] Z. M. Ao, J. Yang, S. Li and Q. Jiang, “Enhancement of CO detection in Al doped graphene”, Chemical Physics Letters, Vol.461, pp.276-279, (2008).
[50] M. Gautam and A. H. Jayatissa, “Ammonia gas sensing behavior of graphene surface decorated with gold nanoparticles”, Solid-State Electronics, Vol.78, pp.159-165, (2012).
[51] S. Kumara, N. McEvoya, T. Lutza, G. P. Keeleya, N. Whitesidea, W. Blaua and et al., “Low temperature graphene growth”, ECS Transactions, Vol.5, pp.175-181, (2009).
[52] G. Giovannetti, P. A. Khomyakov, G. Brocks, V. M. Karpan, J. Brink and P. J. Kelly, “Doping graphene with metal contacts”, Physical Review Letters, Vol.101, pp.026803-026806, (2008).
[53] S. Ryu, L. Liu, S. Berciaud, Y. J. Yu, H. Lu, P. Kim, G. W. Flynn and L. E. Brus, “Atmospheric Oxygen Binding and Hole Doping in Deformed Graphene on a SiO2 Substrate”, Nano Letters, Vol.10, pp.4944-4951, (2010).