本研究之主要目的在於新穎不含金屬電極觸媒材料的製程開發及其在直接甲醇燃料電池(DMFC)電極的應用。在材料合成方面，吾人延續本實驗室近幾年在以傳統水熱法製備雜原子(如氮)摻雜孔洞性碳材(CPMs)的研究，主要利用含氮量極高的三聚氰胺(C3H6N6)與甲醛(CH2O)形成三聚氰胺甲醛樹脂低聚物(MFRO)作為主要碳源，並分別以三區塊共聚物界面活性劑(P123)及水玻璃(NaSi3O7)作為軟模板及硬模板，利用共凝聚法(co-condensation)搭配微波輔助合成方式製備高含氮量之孔洞碳材(N-CPMs)。吾人藉由調控不同的樣品微波前處理溫度(60  100 oC)與時間(1  24 h)，改變MFRO與軟、硬模板間的聚合程度，進而影響碳矽(C-Si)複合結構，在經高溫(800  1000 oC)碳化，隨後以強酸溶液除去氧化矽模板，最後經水洗乾燥之後得到不同氮含量及電子與物化特性之N-CPMs。
隨後，吾人並透過不同光譜及分析實驗技術，如粉末x-光繞射、氮氣等溫吸/脫附、元素分析、熱重分析、x-光光電子能譜等，對各樣品進行物化特性鑑定。最後並利用此類未負載金屬觸媒的N-CPM做為DMFC陰極電極材料，以線性掃描伏安法(LSV)量測其對氧氣還原反應(ORR)之催化效能，並將之與傳統水熱合成法所製備之N-CPM比較。研究發現，改變上述微波輔助合成參數導致樣品中有不同氮物種的分佈，一般而言，在不同的合成溫度下，吡啶型氮(pyridinic-N；簡稱為N6)和吡咯型氮(pyrrolic-N；簡稱N5)的含量都相對較高(各約佔40%)，而四級型氮(quarternary-N；或稱為季胺型氮，簡稱NQ)和氧化吡啶型氮(pyridinic-N+-O；簡稱NX)的含量相對較低，分別約佔15%及5%。吾人比較在相同最後碳化溫度(900 oC)下，微波前處理溫度與時間對N-CPM中氮物種分佈之影響，發現NX物種的含量較不隨合成參數的變化而改變。在較低前處理溫度(60 oC)下，N6的含量明顯隨處理時間的增加而上升，N5含量則略為下降。而在提高溫度至100 oC時，N6及N5含量下降而NQ則上升，然而此時增加處理的時間(1  24 h)，N6的含量變化不大，約維持在45%左右，N5含量由43%降至約30%，而NQ則明顯由12%增加至約20%。由此可見，在較高前處理溫度下延長前處理時間會將部分N6及N5轉變為NQ，說明後者有相對較高的熱力學穩定性。藉由調控不同碳氮鍵結的比例，發現當NQ含量少於10%時N-CPM之ORR催化活性明顯變差，由於N6和NQ被認為是主要的活性位，吾人藉而推論NQ為主要的活性中心，而N5、N6則有協同效應，擔任傳遞電子的角色。在材料結構方面，改變微波溫度可調控材料之孔洞分佈，在低溫(60 oC)進行前處理可調控孔徑分佈在20 ~ 40 nm，而在高溫(100 oC)時材料孔徑則在20 nm以下。
有別於傳統水熱法，利用微波輔助合成除可大量縮短製程時間外，亦可增進材料之結構穩定性，也因而提升其ORR活性。吾人將在微波前處理溫度提高至100 oC，並經高溫(1000 oC)碳化後，N-CPM之表面積仍有206 m2/g，且其含氮量高達7 wt%。在活性方面在0.3V電壓下，經由LSV所測得之電流密度為0.49 mA，遠優於由水熱法製備之樣品(0.11 mA)。即便上述催化活性表現略於常見的商用鉑基(Pt-based)觸媒，但以此不含金屬之N-CPM而論，除可以完全避免陰極甲醇穿透之疑慮外，並有製備簡易及成本低廉等優點，未來在燃料電池或感測器電極觸媒材料方面有良好的應用前景。

The objectives of this study are the synthesis development and application of novel, metal-free electrocatalyst materials for direct methanol fuel cell (DMFC). In continuation of our previous investigation using the conventional hydrothermal synthesis route to fabricate heteroatom (such as nitrogen) doped carbon porous materials (CPMs), the highly N-doped CPMs report herein was synthesized by first mixing the N-rich ( 66.7%) melamine (C3H6N6) with formaldehyde (CH2O) to form the melamine-formaldehyde resin oligomer (MFRO). By utilizing the MFRO as primary carbon precursor, tri-block copolymer surfactant (P123) as soft template, and sodium silicate (NaSi3O7) as the hard template, various N-CPMs were fabricated by co-condensation method in conjunction with microwave heating. By varying the synthesis parameters, such as the temperature (60  100 oC) and duration (1  24 h) of the microwave pre-treatment, the extent of polymerization between the MFRO and the soft and hard templates may be manipulated, thereby affecting the structural properties of the carbon-silicon (C-Si) composite during carbonization at elevated temperatures (800  1,000 oC). Subsequently, the C-Si composites were subjected to acid leaching with acid (HF) solution to remove the silica template, followed by thorough washing and drying of the resultant substrates. Finally, various N-CPMs with different N content, physicochemical, and electronic properties may be obtained.
The N-CPMs so fabricated were characterized by a variety of different analytical and spectroscopic techniques, such as powdered x-ray diffraction (PXRD), nitrogen adsorption/desorption isotherm measurements, elemental analysis (EA), thermogravimetric analysis (TGA), and x-ray photoelectron spectroscopy (XPS). Finally, these metal-free N-CPMs were utilized as electrocatalysts for DMFC at cathode. Their electrocatalytic performances during oxygen reduction reaction (ORR) were further evaluated by linear sweep voltammetry (LSV) and compared with those prepared by the conventional hydrothermal synthesis method.
It is found that, variations in parameters during the microwave-assisted synthesis procedures lead to changes in the distribution of different N species in the N-CPM catalysts. Among them, pyridinic-N (denoted as N6) and pyrrolic-N (denoted as N5) species have relatively higher (ca. 40% each) contents than the quarternary-N (denoted as NQ; ca. 15%) and oxidized pyridinic-N+-O (denoted as NX; ca. 5%) species. By keeping the final carbonization temperature fix at 900 oC, the effects of microwave pre-treatment temperature and duration time on the distribution of various N species in N-CPMs were investigated by means of XPS. It was found that the NX content is insensitive to the synthesis parameters, as anticipated. Pretreatment at low temperature (60 oC) led to an increase in the amount of N6, which was accompanied by a marginal decrease in N5. Upon lifting the temperature to 100 oC, a notable increase in NQ amount was observed at the expanses of decreasing N6 and N5. Further extending the treatment duration from 1 to 24 h resulted in a decrease in N5 (from 43% to 30%) and a notable increase in NQ (from 12% to 20%) while the amount of N6 remained practically unchanged at ca. 45%. Apparently, the NQ species appears to have a relatively higher thermodynamic stability than N6 and N5. It was found that, the ORR activity decrease rapidly as the NQ content in N-CPM was lower than 10% . Since N6 and NQ species are known to play the key roles during ORR, it is hypothesized that the NQ sites were responsible as the primary active centers while the N5、N6 sites play a synergetic counterpart to proton electron donation. In terms of the textural properties, microwave-assisted synthesis also facilitates a control in the pore structure of N-CPMs, typically, a pore size distribution of ca. 20  40 nm was observed for samples pre-treated at 60 oC and below 20 nm for those treated at 100 oC.
In comparison with the conventional hydrothermal method, microwave-assisted synthesis can not only largely reduce the preparation time of N-CPMs, but also enhance their structural stability, thus, in turn promote a higher ORR activity. For example, when pre-treated at 100 oC for 6 h followed by carbonization at 1000 oC, the resultant N-CPM prepared by the microwave-assisted method is capable of retaining a satisfactory surface area (206 m2/g) as well as high total N content as high as 7 wt%. By means of LSV measurements, a maximum current density of 0.49 mA was observed for this sample during ORR, which is clearly more superior over the sample prepared by hydrothermal method (0.11 mA; under a pre-treatment time of 24 h). Although, the ORR activities observed for these N-CPMs are indeed lower than that of typical Pt-based commercial catalysts, these novel metal-free highly N-doped CPMs not only have a total tolerance over methanol crossover effect, but also can be fabricated more easily and cost-effectively, and thus should have prospective applications as electrocatalyst materials for DMFC and various sensors.

(1) C. F. Schonbein and Ber. Verh, Nat. Ges. Basel., 1838 , 4, 58.
(2) W. R. Grove, Philosophical Transactions, 1843, 133, 91.
(3) L. Mond and C. Langer, Proc. R. Soc. London., 1889, 46, 296.
(4) W. Nernst, Elektrochem, 1899, 6, 41.
(5) E. Baur and H. Preis, Z. Electrochem.,1937, 43, 727.
(6) P. Stonehart, J. Appl. Electrochem., 1992, 22, 995.
(7) K. Scott , W.M. Taama, and P. Argyropoulos, J. Power Sources.,
1999, 79,43.
(8) G. F. McLean, T. Niet, S. Prince-Richard, N. Djilali, Int J
Hydrogen Energ., 2002, 27, 507.
(9) 本間琢也, 上松宏吉, “燃料電池 ”，2011。
(10) 吳培豪，碩士論文，中國文化大學材料科學與奈米科技研究所，”
孔洞性材料負載鉑(Pt)金屬處之製備、特性鑑定與應用”，2006
年6 月。
(11) 吳千舜，碩士論文，國立中央大學化學研究所，”新穎質子交換
膜”，2004 年6 月。
(12) C. S. Tsao, H. L. Chang, U. S. Jeng, J. M. Lin, and T. L. Liu,
Polymer., 2005, 46, 8430.
(13) Y. Shao, G. Yin, and Y. Gao, J. Power Sources, 2007, 171, 558.
(14) Y. Wan, X. Qian, N. Jia, Z. Wang, H. Li, and D. Zhao, Chem.
Mater., 2008, 20, 1012.
(15) D. W. Wang, F. Li, Z. G. Chen, G. Q. Lu, and H. M. Cheng, Chem.
Mater., 2008, 20, 7195.
(16) P. X. Hou, H. Orikasa, T. Yamazaki, K. Matsuoka, A. Tomita, N.
Setoyama, Y. Fukushima, and T. Kyotani, Chem. Mater., 2005, 17,
5187.
(17) Z. Leia, L. Ana, L. Danga, M. Zhaoa, J. Shib, S. Bai, and Y. Caoa,
Micropor. Mesopor. Mater., 2009, 119, 30.
(18) 詹靖儀，碩士論文，國立成功大學化學工程研究所，”聚苯胺衍
生氮摻雜中空球狀中孔洞碳材之製備鑑定與於直接甲醇燃料電
池觸媒之應用”，2010 月6 月。
131
(19) R. Czerw, M. Terrones, J. C. Charlier, X. Blase, B. Foley, R.
Kamalakaran, N. Grobert, H. Terrones, D. Tekleab, P. M. Ajayan,
W. Blau, M. Ruhle, and D. L. Carroll, Nano Lett., 2001, 1, 457.
(20) P. H. Matter and U. S. Ozkan, Catal. Lett., 2006, 109, 115.
(21) J. R. Pels, F. Kapteijn, J. A. Moulijn, Q. Zhu, and K. M. Thomas,
Carbon, 1995, 33, 1641.
(22) P. H. Matter, L. Zhang, and U. S. Ozkan, J. Catal., 2006, 239, 83.
(23) S. M. Lyth, Y. Nabae, S. Moriya,S. Kuroki, M.A. Kakimoto, J. I.
Ozaki, and S. Miyata, J. Phys. Chem. C., 2009, 113, 20148.
(24) Z. Lei, M. Zhao, L. Dang, L. An, M. Lu, A. Y. Lo, N. Yub, and S. B.
Liu, J. Mater. Chem., 2009, 19, 5985.
(25) A. L. M. Reddya, N. Rajalakshmib, and S. Ramaprabhua, Carbon,
2008, 46, 2.
(26) R. Bashyaml and P. Zelenay, Nature, 2011, 443, 63.
(27) G. Wu, L. Li, J. H. Li, and B. Q. Xu, Carbon, 2005, 43, 2579.
(28) C. P. Ewels and M. Glerup, J. Nanosci. Nanotechnol., 2005, 5,
1345.
(29) E. G. Wang, J. Mater. Res., 2006, 21, 2767.
(30) M. Glerup, J. Steinmetz, D. Samaille, O. Stephan, S. Enouz, A.
Loiseau, S. Roth, and P. Bernier, Chem. Phys. Lett., 2004 , 387,
193.
(31) J. C. Hummelen, B. Knight, J. Pavlovich, R. Gonzalez, and F. Wudl,
Science, 1995, 269, 1554.
(32) M. Terrones, H. Terrones, N. Grobert, W. K. Hsu, Y. Q. Zhu, J. P.
Hare, H. W. Kroto, D. R. M. Walton, P. Kohler-Redlich, M. Ruhle,
J. P. Zhang, and A. K. Cheetham, Appl. Phys. Lett., 1999, 75, 3932.
(33) M. Glerup, M. Castignolles, M. Holzinger, G. Hug, A. Loiseau, and
P. Bernier, Chem. Commun., 2003, 2542.
(34) S. Maldonado, S. Morin, and K. J. Stevenson, Carbon, 2006, 44,
1429.
(35) C. B. Cao, F. L. Huang, C. T. Cao, J. Li, and H. Zhu, Chem. Mater.,
2004, 16, 5213.
(36) Y. Shao, J. Sui, G. Yin, and Y. Gao, Appl. Catal. B: Environ., 2008,
79, 89.
132
(37) J. Lee, S. Yoon, T. Hyeon, S. M. Oh, and K. B. Kim, Chem.
Commun., 1998, 2177.
(38) M. Kuno, T. Naka, E. Negihsi, H. Matsui, O. Terasaki, R. Ryoo,
and N. Toyota, Syn. metals, 2003, 721.
(39) H. Zhou, S. Zhu, M. Hibino, I. Honma, and M. Ichihara, Adv.
Mater., 2003, 15, 2107.
(40) M. Guisnet and P. Magnoux, Appl. Catal., 1989, 54, 1.
(41) J. H. Knox, B. Kaur, and G. R. Millward, J. Chromatogr., 1986,
352, 3.
(42) M. Kaneda, T. Tsubakiyama, A. Carlsson, Y. Sakamoto, T. Ohsuna,
O. Terasaki, S. H. Joo, and R. Ryoo, J. Phys. Chem. B., 2002, 106,
1256.
(43) R. Ryoo, S. H. Joo, and S. Jun, J. Phys. Chem. B., 1999, 103, 7743.
(44) S. Jun, S. H. Joo, R. Ryoo, M. Kruk, M. Jaroniec, Z. Liu, T.
Ohsuna, and O. Terasaki, J. Am. Chem. Soc., 2000, 122, 10712.
(45) T. Ohkubo, J. Miyawaki, K. Kaneko, R. Ryoo, and N. A. Seaton, J.
Phys. Chem. B., 2002, 106, 6523.
(46) S. H. Joo, R. Ryoo, M. Kruk, and M. Jaroniec, J. Phys. Chem. B.,
2002, 106, 4640.
(47) S. H. Joo, S. J. Choi, I. Oh, J. Kwak, Z. Liu, O. Terasaki, and R.
Ryoo, Nature, 2001, 412, 169.
(48) S.H. Joo, R. Ryoo, M. Kruk, and M. Jaroniec, Chem. Commun.,
2001, 349.
(49) Mauro Iannelli, “Microwave-assisted Synthesis of Monomeric
and Polymericamides", 2006.
(50) J. S. Schanche, Mol. Diversity, 2003, 7, 293.
(51) J. B. Koo, N. Jiang , S. Saravanamurugan, M. Bejblova, Z.
Musilova, J. Cˇejka , and S. E. Park, J. Catal., 2010, 276, 327.
(52) X. Zhao, H. Wang, C. Kang, Z. Sun, G. Li, and X. Wang, Micropor.
Mesopor. Mater., 2012, 151 , 501.
(53) T. Benamor, L. Vidal, B. Lebeau, and C. Marichal, Micropor.
Mesopor. Mater., 2012, 153, 100.
(54) Y. Cao, H. J. Wei, Z. N. Xia, Trans. Nonferrous Met. Soc. China,,
2009, 19, 656.
133
(55) (a) A. J. Bard and L. R. Faulkner, in “Electrochemical Methods:
Fundamentals and Applications”, Wiley, New York, 2001; (b) W.
Chen, and S. W. Chen, Angew. Chem. 2009, 121, 4450; Angew.
Chem. Int. Ed., 2009, 48, 4386.
(56) Y. L. Hsin, K. C. Hwang, and C. T. Yeh, J. Am. Chem. Soc., 2007,
129, 9999.
(57) B. L. Newalkar, S. Komarneni, and H. Katsuki, Chem. Commun.,
2000, 2389.
(58) 陳佳婷，碩士論文，國立臺灣師範大學化學研究所，”高含氮
孔洞碳材的製備及其在燃料電池電池材料之應用”，2010 年7
月。