牟中原臺灣大學：化學研究所施文塵Shih, Wen-ChengWen-ChengShih牟中原指導2007-11-262018-07-102007-11-262018-07-102007http://ntur.lib.ntu.edu.tw//handle/246246/51905本研究利用反應動力學，原位漫反射紅外光譜與氧氣溫度程控脫附等實驗技術以及理論反應模型計算研究金銀合金附載於中孔洞MCM-41材料應用於異相催化一氧化碳氧化反應，並探討可能之催化反應行為與機制。 針對利用一鍋法合成具顆粒較小之金銀合金材料，在反應溫度為80度時，其高的反應活性與罕見的一級反應級數表現可能與在合金表面上，吸附態的一氧化碳與氧氣以極為鄰近的位置，進行非解離與非競爭吸附的Langmuir-Hinshelwood反應行為。相對小的反應活化能，幾乎可以忽略的一氧化碳與氧氣表面覆蓋率以及隨著反應溫度上昇，伴隨的氣體脫附現象，皆為催化活性隨著反應溫度呈現先上昇，下降再上昇異常行為的可能原因。而在高溫時，合金催化劑表現類似於單金屬催化劑，暗示隨著不同溫度，合金具有不同的反應行為與參與催化反應的活性位置。 針對利用兩步法合成具有顆粒較大之金銀合金材料，在反應溫度為80度時，其高的反應活性與一級反應級數表現被實驗證實在合金表面吸附態的一氧化碳與氧氣在極靠近的位置進行非解離與非競爭或競爭吸附的Langmuir-Hinshelwood 反應行為。隨著反應溫度增加，反應活性下降的原因可能與吸附態一氧化碳和氧氣進行脫附行為或氧氣進行解離式吸附有關。 在室溫下水溶液中，利用微胞保護之金與銀奈米顆粒，其在金屬與微胞界面中，三環芳香烴可進行均相催化的氫化反應，實驗證實催化活性具有明顯的粒子大小控制效應而氫化反應的可能反應行為為奈米顆粒扮演類似具有傳導電子的奈米電極角色。金與銀奈米顆粒催化活性的差異與金屬親近電子與釋放電子至周圍水溶液環境的能力有關。The heterogeneously catalytic CO Oxidation with Au-Ag alloy deposited on inert and acidic mesoporous aliminosilicate MCM-41 support, prepared by either one-pot or two-step procedure, has been investigated in terms of the experimental kinetics, in-situ DRIFTS, O2 pulse adsorption, O2-TPD and theoretical reaction modeling. For one-pot/3:1 Au-Ag/MCM-41 alloy catalyst, the unexpectedly high catalytic activity at 80oC may be associated with the non-dissociative and non-competitive adsorption Langmuir-Hinshelwood model between CO and O2 species in intimate proximity on the alloy surface. The small activation energy, negligible surface coverage and desorption with raising temperature for both CO and O2 may give rise to the unusual behavior in reaction rate above 80oC. At higher temperature, the different reaction behavior and/or active site for CO oxidation could be altered, which may behave like supported monometallic metal catalyst. For two-step/5:1 Au-Ag/MCM-41 catalyst, the high catalytic activity at 80oC could be due to non-dissociative and non-competitive or competitive Langmuir-Hinshelwood model between adsorbed CO on Au and O2 on Ag in close proximity of Au-Ag alloy surface as the RDS. The decrease in CO conversion with the increasing temperature could be caused by either desorption of both CO and O2 or dissociative adsorption for O2 on the Au-Ag alloy surface. Anthracene hydrogenation in aqueous micellar solutions at room temperature is homogeneously catalyzed by ionic-surfactant-protected Au and Ag nanoparticles with well-controlled particle sizes. A remarkable size-dependence of catalytic activity is derived. The difference in the optical property of meal nanoparticles could be related to the charging of their surfaces, indicating that both the metal nanoparticles play a role as the nanoelectrode storing electrons from hydrides. The behavior about the electron transfer-relaying effects of metal nanoparticles is proposed for the hydrogenation reaction.謝辭 III 中文摘要 V Abstract VI Contents VII List of Figures XI List of Tables XX List of Schemes XXII CHAPTER 1 The Kinitics and in-situ DRIFTS Study of CO Oxidation on Au-Ag/MCM-41 Alloy Nanocatalyst 1 1. Introduction 2 1.1 Chemical and Physical Properties of Gold 2 1.2 Preparation for Supported Gold Catalysts 2 1.2.1 Impregnation 2 1.2.2 Coprecipitation 3 1.2.3 Deposition-Precipitation 3 1.2.4 Vapor-Phase Deposition and Grafting 4 1.2.5 Ion-Exchange and Preparation of Gold/Zeolite Catalysts 4 1.3 CO and O2 Adsorption on Gold Surface 5 1.4 The Influence on CO Oxidation 5 1.4.1 Preparation Effect 5 1.4.2 Support Effect 6 1.4.3 Particle Size Effect 6 1.5 Kinetics and Mechanism 6 1.6 Literatures Reviews for Reaction Kinetics on CO Oxidation 9 1.7 Issue and Motivation for Au-Ag/MCM-41 Alloy on CO oxidation 13 2. Experimental 14 2.1. Catalysts and Reactants 14 2.2. Rates and reaction orders: The Power Rate Law 17 2.3. Kinetic Measurements 18 2.4. In-Situ Diffuse Reflectance Infrared Fourier Transform Spectroscopy 19 2.5. TEM and Powder X-ray Diffraction (XRD) Characterization 20 3. Results 21 3.1 Physical properties for one-pot and two-step Au-Ag/MCM-41 by XRD and TEM 21 3.2 CO Conversion XCO for one-pot/3:1 and two-step/5:1 Au-Ag/MCM-41 catalysts 23 3.3 The Kinetics for one-pot Au-Ag/MCM-41 catalyst 24 3.3.1 The Kinetics for one-pot/3:1 Au-Ag/MCM-41 catalyst 24 3.3.1.1 CO Conversion for one-pot/3:1 Au-Ag/MCM-41 catalyst 25 3.3.1.2 The CO reaction orders for one-pot/3:1 Au-Ag/MCM-41 catalyst 27 3.3.1.3 The O2 reaction orders for one-pot/3:1 Au-Ag/MCM-41 catalyst 28 3.3.2 The Kinetics for one-pot monometallic Au/MCM-41 29 3.3.2.1 CO Conversion for one-pot monometallic Au/MCM-41 29 3.3.2.2 The CO and O2 reaction orders for one-pot monometallic Au/MCM-41 30 3.3.3 The Kinetics for one-pot monometallic Ag/MCM-41 32 3.3.3.1 CO Conversion for one-pot/3:1 monometallic Ag/MCM-41 32 3.3.3.2 The CO and O2 reaction orders for one-pot monometallic Ag/MCM-41 33 3.3.4 Summary for kinetics data 35 3.3.4.1 Kinetics data summary for one-pot/3:1 Au-Ag/MCM-41 35 3.3.4.2 Kinetics data summary for one-pot monometallic Au and Ag/MCM-41 35 3.3.4.3 The Arrhenius plots of CO oxidation for bimetallic one-pot/3:1 Au-Ag/MCM-41, monometallic Au/MCM-41 and Ag/MCM-41 36 3.4 The Kinetics for two-step/5:1 Au-Ag/MCM-41 catalyst 37 3.4.1. CO Conversion for two-step/5:1 Au-Ag/MCM-41 catalyst 37 3.4.2 The CO reaction orders for two-step/5:1 Au-Ag/MCM-41 catalyst 38 3.4.3 The O2 reaction orders for two-step/5:1 Au-Ag/MCM-41 catalyst 39 3.4.4 Kinetics data summary for two-step Au-Ag/MCM-41 40 3.5 In-situ DRIFTS measurements 42 3.5.1 Spectra under CO/He on pure one-pot MCM-41 support 43 3.5.2 Spectra under CO/He on one-pot Au-Ag/MCM-41 with Au/Ag loading ratios 46 3.5.3 Spectra under CO/He on one-pot/3:1 Au-Ag/MCM-41 48 3.5.4 Spectra under reaction condition on one-pot/3:1 Au-Ag/MCM-41 catalyst 49 3.5.5 Spectra under CO/He on two-step/5:1 Au-Ag/MCM-41 catalyst 52 3.5.6 Spectra under reaction condition on two-step/5:1 Au-Ag/MCM-41 catalyst 53 3.6 O2 pulse adsorption and O2-TPD for one-pot and two-step Au-Ag/MCM-41 56 4. Discussion 59 4. Conclusions 70 References 71 CHAPTER 2 Reaction Modeling for CO Oxidation on One-pot/3:1 Au-Ag/MCM-41 Nanocatalyst 75 1. Introduction 76 2. Experimental 77 2.1 SAS 9.1.3 service pack 4 for Windows 77 2.2 Programming and syntax for SAS software 78 3. Results 80 3.1 Description of all possible models for the surface reaction 80 3.1.1 Eley-Rideal model as R.D.S. 80 3.1.2 Adsorption model as R.D.S. 84 3.1.3 Langmuir-Hinshelwood model as R.D.S. 87 3.2 Theoretical Reaction Modeling 93 4. Discussions 105 5. Conclusions 124 References 125 CHAPTER 3 Electron Transfer-Induced Hydrogenation of Anthracene Catalyzed by Au and Ag Nanoparticles 127 1. Introduction 128 2. Experimental 133 2.1 Materials 133 2.2 Preparation of Metal Nanoparticles 133 2.3 Instruments and Methods 135 3. Results and Discussions 136 3.1 The formation of Au and Ag nanoparticles 136 3.1.1 Anionic and cationic surfactants 136 3.1.2 Concentration of surfactants 137 3.1.3 Counter ion of surfactants 139 3.2 The catalytic hydrogenation of anthracene 146 3.2.1 Hydrogenation of anthracene by Au and Ag nanopartocles 146 3.2.2 Product identification by 1H-NMR 150 3.2.3 Size effect for catalytic activity 152 3.2.4 Anthracene derivatives and possible reaction mechanism study 157 4. Conclusions 163 References 1642154631 bytesapplication/pdfen-US異相催化一氧化碳氧化反應金銀合金觸媒反應動力學反應模型計算均相催化氫化反應Heterogeneous CatalysisCO OxidationAu-Ag Alloy CatalystReaction KineticsReaction ModelingHomogeneous CatalysisHydrogenationthesishttp://ntur.lib.ntu.edu.tw/bitstream/246246/51905/1/ntu-96-D90223026-1.pdf