Title Page
ABSTRACT
국문 초록
PREFACE
Contents
CHAPTER 1. H₂O₂ Heterolysis on Bimetallic Sulfides 52
1.1. Introduction 52
1.2. Experimental 56
1.2.1. Catalysts 56
1.2.2. Characterizations 57
1.2.3. Reactions 59
1.3. Results and discussion 61
1.3.1. Catalysts 61
1.3.2. Activity and rate-determining step 74
1.3.3. Heterogeneous catalysis and recyclability 82
1.3.4. Adaptability and selectivity 89
1.4. Conclusion 98
CHAPTER 2. H₂O₂ Heterolysis on Monometallic Sulfide Enclosed by SiO₂ 101
2.1. Introduction 101
2.2. Experimental 106
2.2.1. Catalysts synthesis 106
2.2.2. Characterizations 107
2.2.3. Reactions 109
2.2.4. Kinetic assessments 110
2.3. Results and discussion 111
2.3.1. Generic properties of the catalysts 111
2.3.2. Proofs of NLA elevation with SiO₂ encapsulation[이미지참조] 120
2.3.3. Proofs of ELA reduction with SiO₂ encapsulation[이미지참조] 127
2.3.4. Insights into the routes of H₂O₂ fragmentation with SiO₂ encapsulation 134
2.3.5. Proofs of reduced Niδ⁺ leaching with SiO₂ encapsulation[이미지참조] 142
2.4. Conclusion 148
CHAPTER 3. H₂O₂ Homolysis on Zirconium Oxides Supported by Functional Carbons 151
3.1. Introduction 151
3.2. Experimental 158
3.2.1. Chemicals 158
3.2.2. Reactions: procedures 159
3.2.3. Computations 160
3.2.4. Materials 161
3.2.5. Characterizations 162
3.2.6. Reactions: analyses 165
3.3. Results and discussion 168
3.3.1. Properties of Zr-MOFs 168
3.3.2. Generic properties of pyrolyzed Zr-MOFs 177
3.3.3. Acidic properties of pyrolyzed Zr-MOFs 193
3.3.4. Control reactions and characterizations 208
3.3.5. Kinetic parameters and recyclabilities 230
3.4. Conclusion 255
CHAPTER 4. H₂O₂ Homolysis for ˙OH-mediated Cl˙ Evolution on Functional UiO-66 259
4.1. Introduction 259
4.2. Experimental 266
4.2.1. Catalysts synthesis 266
4.2.2. Characterizations 268
4.2.3. Computations 274
4.2.4. Reactions 276
4.3. Results and discussion 279
4.3.1. Generic properties of the MOFs 279
4.3.2. Compositional properties of the MOFs 288
4.3.3. Acidic properties of the MOFs 306
4.3.4. Viability of ˙OH→Cl˙SUP: EPR spectroscopy and computations[이미지참조] 318
4.3.5. Viability of ˙OH→Cl˙SUP: reactions and computations[이미지참조] 329
4.3.6. Kinetic parameters and practicalities of the MOFs 344
4.4. Conclusion 362
CHAPTER 5. Overall conclusion 366
5.1. Conclusions and perspectives 366
REFERENCES 369
Table 1.1. Coefficients used to depict CO₂ adsorption isotherms of the catalysts via Toth fittings. 68
Table 2.1. Textural and compositional traits of the catalysts. 112
Table 2.2. Locations and relative abundance of surface phases assigned in XPS spectra of the catalysts in the Ni 2p and Si 2p regime. 123
Table 2.3. Locations and relative abundance of surface phases assigned in XPS spectra of the catalysts in the S 2p and O 1s regime. 126
Table 2.4. Apparent rate constants (kAPP) of the catalysts in degrading phenol.[이미지참조] 130
Table 2.5. Parameters utilized to simulate EPR spectra of reaction mixtures. 136
Table 2.6. Secondary rate constants of scavengers used to quench ˙OH, ˙OOH, or O₂˙⁻. 140
Table 3.1. Properties of UiO-66, UiO-66-NH₂, and UiO-66-SO₃H. 170
Table 3.2. Molar compositions of DMF and BDC-NH₂ (or BDC-SO₃H) relative to that of BDC inherent to UiO-66, UiO-66-NH₂, or UiO-66-SO₃H. 175
Table 3.3. Properties of CUiO-₆₆, CUiO-₆₆-NH₂, and CUiO-₆₆-SO₃H.[이미지참조] 182
Table 3.4. Coefficients utilized to simulate CO isotherms for the catalysts. 199
Table 3.5. Coefficients utilized to simulate CO₂ isotherms for the catalysts. 202
Table 3.6. TMAX values, slopes, and regression factors (R²) used to plot 'ln (β/TMAX²) versus 1/TMAX' for the catalysts.[이미지참조] 205
Table 3.7. Apparent rate constants (kAPP) of reaction runs.[이미지참조] 215
Table 3.8. Parameters utilized to simulate EPR spectra of reaction solutions. 219
Table 3.9. Secondary rate constants of quenchers in terminating ˙OH, ˙OOH, or O₂˙⁻. 226
Table 3.10. Amounts of Zr, N, and S leached from the catalyst surfaces during recycle runs to degrade phenol. 245
Table 3.11. SN₂, VMESO, VMICRO, and VPORE values for the catalysts subjected to recycle runs to degrade phenol.[이미지참조] 253
Table 4.1. Textural and compositional properties of UiO-66 and UiO-66-Cl. 286
Table 4.2. Compositions of DMF and dodecanoate relative to that of BDC (or BDC-Cl) for UiO-66 or (UiO-66-Cl). 290
Table 4.3. Numbers of missing organic strut (X) and DMF coordinated to μ₃-OH (Y) for UiO-66 or UiO-66-Cl. 291
Table 4.4. Equivalent points of UiO-66 and UiO-66-Cl subjected to titration with the use of NaOH as a titrant. 294
Table 4.5. Coefficients used to simulate H₂O isotherms for UiO-66 and UiO-66-Cl. 299
Table 4.6. Binding energies and concentrations of surface phases observed in Zr 3d and C 1s XP spectra of UiO-66 and UiO-66-Cl. 303
Table 4.7. Binding energies and concentrations of surface phases observed in O 1s, N 1s, and Cl 2p XP spectra of UiO-66 and UiO-66-Cl. 304
Table 4.8. Coefficients used to simulate CO₂ isotherms for UiO-66 and UiO-66-Cl. 308
Table 4.9. Coefficients used to simulate CO isotherms for UiO-66 and UiO-66-Cl. 310
Table 4.10. Quantification of surface sites available to homolytic H₂O₂ scission and/or ˙OH→Cl˙SUP for UiO-66 and UiO-66-Cl.[이미지참조] 312
Table 4.11. Apparent reaction rate constants (kAPP) of control reactions[이미지참조] 316
Table 4.12. Parameters used to simulate EPR spectra of reaction solutions and mixtures. 322
Table 4.13. Relative abundance of DMPO-OH, DMPO-OOH, HDMPO-OH, or DMPO-X adducts simulated for EPR spectra of reaction solutions/mixtures. 325
Table 4.14. Quantities of Zr/Cl, Mn/N, and Fe/S leached from UiO-66/UiO-66-Cl, Mn oxide-N, and Fe oxide-S, respectively, during phenol degradation runs. 349
Table 4.15. Lengths of four Zr-OA bonds (dZr-OA; A=1-4) present in the MOFs simplified for DFT calculations.[이미지참조] 352
Figure 1.1. (A) Illustration of proposed H₂O₂ scission cycle mediated by metal species (M) with the oxidation state (δ) of ≤ 2, wherein § or ¥ indicates the potential elementary step to direct H₂O₂... 54
Figure 1.2. HRTEM images and SAED patterns of NiCO₂S₄ (A and E), NiCO₂S₄ (B and F), NiS (C and G), and CoS (D and H). (I) XRD patterns of the catalysts (JCPDF No. of 01-077-1624 for NiS;... 63
Figure 1.3. XP spectra of the catalysts in Ni 2p ₃/₂ (A, C, and E) and CO 2p ₃/₂ regions (B, D, and F). Black lines indicate raw XP spectra, whereas grey empty circles indicate fitted XP spectra. Black...[이미지참조] 65
Figure 1.4. (A) Quantities of CO-accessible Lewis acidic sites innate to the catalysts (NCO) and their isosteric heats of CO₂ adsorption (-QST). (B) Relative abundance of surface S²⁻ species (%)...[이미지참조] 67
Figure 1.5. (A-D) CO₂ adsorption isotherms of the catalysts fitted using Toth equation. In (A)-(D), black, red, and blue symbols indicate CO₂ adsorption isotherms obtained at -20 °C, 0 °C, and... 69
Figure 1.6. (A-D) XP spectra of the catalysts in S 2p regions. Black lines indicate raw XP spectra, whereas grey empty circles indicate fitted XP spectra. Black and red/green/blue empty circles denote... 71
Figure 1.7. Linear sweep voltammograms of the catalysts. Analysis conditions: graphite (working electrode) coated with 0.2 g of catalyst, Ag/AgCl/3M KCl (reference electrode), and Pt wire... 73
Figure 1.8. H₂O₂ evolution profiles of the catalysts (amount of H₂O₂ produced versus time) obtained at 1 V (green empty triangle), 2 V (green half-filled triangle), or 3 V (solid symbols). Dotted... 75
Figure 1.9. (A) Phenol degradation profiles (phenol conversion (XPHENOL) versus time) obtained at 1-3 V in the absence of the catalyst. (B) H₂O₂ scission profiles (H₂O₂ conversion (XH₂O₂) versus...[이미지참조] 76
Figure 1.10. (A) Background-corrected H₂O₂ scission profiles of the catalysts (H₂O₂ conversion (XH₂O₂) versus time) obtained with the use of different H₂O₂ quantities (2.6 mmol of H₂O₂ for all...[이미지참조] 78
Figure 1.11. (A) Initial H₂O₂ scission rates (-rH₂O₂, ₀) of the catalysts with the use of 2.6 mmol of H₂O₂. (B) -rH₂O₂ values of NiCO₂S₄ with the use of 2.1 mmol, 2.3 mmol, or 2.6 mmol of H₂O₂ as the...[이미지참조] 79
Figure 1.12. Phenol decomposition profiles (concentration of phenol degraded (C*PHENOL) versus time) obtained via filtration runs in the absence (blank) or the presence of the catalysts. Reaction...[이미지참조] 83
Figure 1.13. Background-corrected phenol degradation profiles of (A) NiS and (B) NiCO₂S₄ obtained during the initial (1st cycle) and recycle runs (2nd and 3rd cycles) at 3 V. Fittings of reaction...[이미지참조] 85
Figure 1.14. Background-corrected phenol degradation profiles (phenol conversion (XPHENOL) versus time) of (A) NiCO₂S₄ and (B) CoS obtained during the initial (1st cycle) and recycle runs (2nd...[이미지참조] 86
Figure 1.15. Initial phenol degradation rates (-rPHENOL, ₀) of the catalysts and their loss of Ni or Co (mol. %) via leaching during recycle runs: (A) NiS, (B) NiCO₂S₄, (C) NiCO₂S₄, and (D) CoS. -...[이미지참조] 87
Figure 1.16. (A) Background-corrected aniline degradation profiles (aniline conversion (XANILINE) versus time) of NiCO₂S₄ and NiCO₂S₄ obtained at 3 V. (B) Fittings of reaction data to pseudo-1st-order...[이미지참조] 90
Figure 1.17. Intermediates observed during degradation runs of phenol/aniline on Ni₂COS₄/NiCO₂S₄ at 3V. Degradation pathways of phenol (A-B) and aniline (C-E) were conjectured... 91
Figure 1.18. (A) Background-corrected degradation profiles of (A) aniline (aniline conversion (XANILINE) versus time) and (B) phenol (phenol conversion (XPHENOL) versus time) for NiCO₂S₄ at 3 V...[이미지참조] 93
Figure 1.19. (A) Initial degradation rates of phenol (-rPHENOL, ₀) and aniline (-rANILINE, ₀) for NiCO₂S₄ at 3V in the presence of scavenging agent (1,4-benzoquinone or guaiacol). -rPHENOL, ₀ of...[이미지참조] 94
Figure 1.20. (A-D) Phenol degradation profiles (phenol conversion (XPHENOL) versus time) of the catalysts obtained with the use of different H₂O₂ quantities. XPHENOL values acquired after 8 hours of...[이미지참조] 96
Figure 1.21. Schematic illustration for H₂O₂ heterolysis on bimetallic sulfides. 99
Figure 2.1. (A) Illustration of the electro-Fenton set-up, where IrO₂-coated titanium (IrO₂/Ti) and NiS/Ni₉S₈ (or NiS/Ni₉S₈-SiO₂) served as the anode (*) and cathode (**), respectively. In the anode,... 104
Figure 2.2. XRD patterns of NiS/Ni₉S₈ (A) and NiS/Ni₉S₈-SiO₂ (B) as-synthesized or collected post the 3rd cycle of phenol degradation recycle runs. In (A-B), reflections shown with black solid... 113
Figure 2.3. HRTEM images of NiS/Ni₉S₈ (A-B) and NiS/Ni₉S₈-SiO₂ (C-D) with d spacing indexed to the reflection for rhombohedral NiS (JCPDF No. of 01-086-2281) or orthorhombic Ni₉S₈... 115
Figure 2.4. HRTEM and EDX mapping images of NiS/Ni₉S₈-SiO₂ as-synthesized, in which NiS/Ni₉S₈ particulates were surrounded by SiO₂ shells via entire (A-F) or partial encapsulation (G).... 116
Figure 2.5. FE-SEM and EDX mapping images of NiS/Ni₉S₈ as-synthesized (A-D) or collected post the 3rd cycle of phenol degradation recycle runs (E-G).[이미지참조] 118
Figure 2.6. FE-SEM and EDX mapping images of NiS/Ni₉S₈ as-synthesized (A-D) or collected post the 3rd cycle of phenol degradation recycle runs (E-G).[이미지참조] 119
Figure 2.7. XPS spectra of the catalysts in the Ni 2p (A) and Si 2p regions (B), where gray lines and black empty circles indicate raw and fitted XPS spectra, respectively, whereas cyan empty circles denote backgrounds. In (A), empty and solid symbols correspond to surface... 122
Figure 2.8. XPS spectra of the catalysts in the O 1s domains, where gray lines and black empty circles indicate raw and fitted XPS spectra, respectively, whereas cyan empty circles denote backgrounds.... 125
Figure 2.9. (A) Linear sweep voltammograms of the catalysts, where the electric potential (E) was scanned from 0 V to -1 V, during which O₂ can be converted to H₂O₂ and H₂O via 2e⁻ and 4e⁻ transfer routes, respectively. (B) Plots of logarithmic background-corrected,... 128
Figure 2.10. (A) Fittings of background-corrected reaction data to pseudo-1st -order kinetic model (-ln (CPHENOL/CPHENOL, ₀) versus time) to evaluate apparent rate constants (kAPP values in Table 2.4) of...[이미지참조] 131
Figure 2.11. Fittings of background-corrected reaction data to pseudo-1st-order kinetic model to evaluate kAPP values (Table 2.4) of NiS/Ni₉S₈ (A) and NiS/Ni₉S₈-SiO₂ (B) in decomposing phenol...[이미지참조] 133
Figure 2.12. (A) Transitions of DMPO to DMPO-OH (black solid square), HDMPO, HDMPO-OH (red solid circle), DMPO-O₂⁻, or DMPO-OOH (green solid upper triangle). (B) EPR spectra of aqueous mixtures including NiS/Ni₉S₈ (or NiS/Ni₉S₈-SiO₂), H₂O₂, and DMPO,... 135
Figure 2.13. Fittings of background-corrected reaction data to pseudo-1st-order kinetic model to evaluate kAPP values (Table 2.4) of NiS/Ni₉S₈ (A) and NiS/Ni₉S₈-SiO₂ (B) in decomposing phenol in...[이미지참조] 139
Figure 2.14. -rPHENOL, ₀ values of the catalysts in the absence or presence of a scavenger (hydroquinone, catechol, or guaiacol) under the reaction environments detailed in Table 2.4.[이미지참조] 141
Figure 2.15. Plots of phenol conversions (XPHENOL) versus time in the absence (blank for A) or presence of the catalysts (NiS/Ni₉S₈ for B; NiS/Ni₉S₈-SiO₂ for C). In (B-C), NiS/Ni₉S₈ (or NiS/Ni₉S₈-...[이미지참조] 143
Figure 2.16. (A) XPS spectra of the catalysts in the S 2p domains, where gray lines and black empty circles indicate raw and fitted XPS spectra, respectively, whereas cyan empty circles denote backgrounds. In (A), red, green, blue, and purple empty circles correspond to surface... 145
Figure 2.17. Fittings of background-corrected reaction data to pseudo-1st-order kinetic model to evaluate kAPP values (Table 2.4) of NiS/Ni₉S₈ (A) and NiS/Ni₉S₈-SiO₂ (B) in decomposing phenol...[이미지참조] 147
Figure 2.18. Schematic illustration for H₂O₂ heterolysis on monometallic sulfide enclosed by SiO₂. 149
Figure 3.1. Schematic representation of (A) UiO-66, UiO-66-NH₂, and UiO-66-SO₃H, in which Zr oxo-cluster nodes (Zr₆(μ₃₋O)₄(μ₃₋OH)₄ in (B)) are hexa-coordinated to benzene-1,4-dicarboxylate (BDC), 2-NH₂-benzene-1,4-dicarboxylate (BDC-NH₂), and 2-SO₃H-... 153
Figure 3.2. SEM images of (A) UiO-66, (B) UiO-66-NH₂, and (C) UiO-66-SO₃H. (D) XRD patterns of UiO-66, UiO-66-NH₂, and UiO-66-SO₃H. 171
Figure 3.3. N₂ isotherms of (A) UiO-66, (B) UiO-66-NH₂, (C) UiO-66-SO₃H, and their pyrolyzed analogues (CUiO-₆₆ for (D); CUiO-₆₆-NH₂ for (E); CUiO-₆₆-SO₃H for (F)) recorded at -196 °C. In...[이미지참조] 172
Figure 3.4. (A) Illustration of structures for N,N'-dimethylformamide (DMF) and deprotonated organic struts (benzene-1,4-dicarboxylate for BDC; 2-aminobenzene-1,4-dicarboxylate for BDC-NH₂;... 176
Figure 3.5. HRTEM images of the catalysts produced via pyrolysis of UiO-66 (CUiO-₆₆ for (A)), UiO-66-NH₂ (CUiO-₆₆-NH₂ for (B)), and UiO-66-SO₃H (CUiO-₆₆-SO₃H for (C)). In (A)-(C), dLATTICE and...[이미지참조] 178
Figure 3.6. (A) XRD patterns of CUiO-₆₆, CUiO-₆₆-NH₂, and CUiO-₆₆-SO₃H and (B) EPR spectra of the pyrolyzed catalysts at -196 °C. In (A), d(₂₂₀) denotes the average size of ZrO₂ crystallites at the bulk...[이미지참조] 179
Figure 3.7. Surfaces on the major facets implemented to define tetragonal ZrO₂ poly-crystallites, across which surface Zr⁴⁺ species are tetra-, penta-, or hexa-coordinated to adjacent O atoms. 180
Figure 3.8. XP spectra of (A) CUiO-₆₆, (B) CUiO-₆₆-NH₂, and (C) CUiO-₆₆-SO₃H in the Zr 3d regimes. XP spectra of (D) CUiO-₆₆, (E) CUiO-₆₆-NH₂, and (F) CUiO-₆₆-SO₃H in the C 1s regimes. In (A)-(F), gray...[이미지참조] 185
Figure 3.9. XP spectra of (A) CUiO-₆₆, (B) CUiO-₆₆-NH₂, (C) CUiO-₆₆-SO₃H, and those subjected to H₂O₂ scission control runs in the O 1s regimes (CUiO-₆₆ for (D); CUiO-₆₆-NH₂ for (E); CUiO-₆₆-SO₃H for (F)). In...[이미지참조] 187
Figure 3.10. Raman spectra of (A) CUiO-₆₆, (B) CUiO-₆₆-NH₂, and (C) CUiO-₆₆-SO₃H, in which AD/AG(or ID/IG) values indicate to ratios of areas (or intensities) of D sub-bands (defective and/or disordered carbon lattices) relative to those of G sub-bands (ordered carbon lattices)....[이미지참조] 188
Figure 3.11. XP spectra of (A) CUiO-₆₆, (B) CUiO-₆₆-NH₂, and (C) CUiO-₆₆-SO₃H in the N 1s regimes. (D) XP spectrum of CUiO-66-SO3H in the S 2p regime. In (A)-(D), gray solid lines indicate raw spectra,...[이미지참조] 190
Figure 3.12. XANES spectra of (A) CUiO-₆₆, (B) CUiO-₆₆-NH₂, and (C) CUiO-₆₆-SO₃H at the N-K edges, where π* and σ* resonance domains of surface N dopants were found at photon energies of 〈407 eV and〉 407 eV, respectively.[이미지참조] 191
Figure 3.13. Background-subtracted in situ NH₃-DRIFT spectra of tetragonal ZrO₂ at 50 °C and 150 °C. The surface was purged with 3 vol. % O₂/N₂ at 150 °C for an hour before its DRIFT spectrum... 195
Figure 3.14. Area in a per-CO-accessible or in a per-CO₂-accessible site present in the catalyst surface (SADSORBATE) and binding energy of the catalyst surface with CO, CO₂, or NH₃ (EADSORBATE).[이미지참조] 197
Figure 3.15. CO isotherms of (A) CUiO-₆₆, (B) CUiO-₆₆-NH₂, and (C) CUiO-₆₆-SO₃H recorded at -20 °C, 0 °C, and 20 °C. In (A)-(C), dashed lines denote CO isotherms fitted using Toth equation, whose...[이미지참조] 198
Figure 3.16. CO₂ isotherms of (A) CUiO-₆₆, (B) CUiO-₆₆-NH₂, and (C) CUiO-₆₆-SO₃H recorded at -20 °C, 0 °C, and 20 °C. In (A)-(C), dashed lines denote CO₂ isotherms fitted using Toth equation, whose...[이미지참조] 201
Figure 3.17. NH₃-TPD profiles (NH₃ signal versus temperature) of (A-C) CUiO-₆₆, (D-F) CUiO-₆₆- NH₂, and (G-I) CUiO-₆₆-SO₃H, for which NH₃molecules were adsorbed on the catalyst surfaces prior to...[이미지참조] 204
Figure 3.18. Profiles of ln (β/TMAX²) versus 1/TMAX utilized to extract the binding energies of NH₃ with the catalyst surfaces (ENH₃) at 50 °C. TMAX values indicate the peak temperatures of the sub-bands originating from the de-convolution of the NH₃-TPD profiles for the catalysts...[이미지참조] 206
Figure 3.19. H₂O₂ production profiles (quantity of H₂O₂ evolved (NH₂O₂) versus time) of the catalysts at (A) 1 V, (B) 2 V, or (C) 3 V. In (A)-(C), NH₂O₂ values at ≤ 60 minutes of reaction runs were averaged...[이미지참조] 211
Figure 3.20. Fittings of background-subtracted H₂O₂ scission data to pseudo-1st-order kinetic model for determining apparent rate constants of the catalysts (kAPP values in Table 3.7). In (A)-(C),...[이미지참조] 214
Figure 3.21. EPR spectra of reaction solutions (liquid; black lines) obtained from the filtration of reaction mixtures (solid (catalyst) mixed with liquid) using a 0.45 μm-sized PES syringe. The reaction mixture was typically composed of 0.1 g of the catalyst (CUiO-₆₆ for (A);...[이미지참조] 218
Figure 3.22. Profiles of zeta potential versus pH value for mixtures. The mixture typically consisted of 0.02 g of the catalyst, 10 mL of de-ionized H₂O, and 0.005 mmol of Na₂SO₄, and was... 221
Figure 3.23. Fittings of background-subtracted phenol degradation data to pseudo-1st-order kinetic model for determining apparent rate constants of the catalysts (kAPP values in Table 3.7) at 3... 223
Figure 3.24. Background-subtracted, CO₂-accessible site-normalized initial phenol degradation rates (-rPHENOL, ₀, CO₂) of the catalysts at 3 V, for which phenol degradation runs were conducted (A)...[이미지참조] 224
Figure 3.25. Fittings of background-subtracted phenol degradation data to pseudo-1st-order kinetic model for determining apparent rate constants of the catalysts (kAPP values in Table 3.7) in the...[이미지참조] 227
Figure 3.26. Profiles of phenol concentration (CPHENOL) consumed versus time in the absence (blank) and presence of the catalysts at 3 V, for which catalyst-coated cathodes were removed from...[이미지참조] 229
Figure 3.27. (A) Background-subtracted-rPHENOL, ₀, CO₂ values of the catalysts at 1-3 V. (B) Background-subtracted -rPHENOL, ₀, CO₂ values of the catalysts at 3 V and 25-55 °C. Reaction conditions:...[이미지참조] 232
Figure 3.28. Fittings of background-subtracted phenol degradation data to pseudo-1st-order kinetic model for determining apparent rate constants of the catalysts (kAPP values in Table 3.7) at (A)...[이미지참조] 233
Figure 3.29. Fittings of background-subtracted phenol degradation data to pseudo-1st-order kinetic model for determining apparent rate constants of the catalysts (kAPP values in Table 3.7) at 3...[이미지참조] 236
Figure 3.30. Arrhenius plots of the catalysts to extract their energy barriers (EBARRIER, CO₂ or EBARRIER, CO) and CO₂-/CO-dictated pre-factors (kAPP, ₀, CO₂ or kAPP, ₀, CO) at 3 V and 25-55 °C, for which...[이미지참조] 237
Figure 3.31. Energetics on surface (101) facet for protonated tetragonal ZrO₂ cluster (t-(ZrO₂)₄; Zr for yellow; O for red; H for gray) subjected to (A) exothermic dissociative H₂O adsorption (t-... 239
Figure 3.32. Fittings of background-subtracted phenol degradation data to pseudo-1st -order kinetic model for determining apparent rate constants of the catalysts (kAPP values in Table 3.7) at (A)...[이미지참조] 243
Figure 3.33. (A) Illustration of ˙OH-mediated phenol degradation pathways, where the intermediates shown with m/z values were identified using the LC-MS technique in negative mode,... 244
Figure 3.34. XRD patterns of the catalysts as-synthesized and those subjected to recycle runs to degrade phenol (CUiO-₆₆ for (A); CUiO-₆₆-NH₂ for (B); CUiO-₆₆-SO₃H for (C)). In (A)-(C), facets shown with...[이미지참조] 246
Figure 3.35. SEM images of the catalysts as-synthesized and those subjected to recycle runs to degrade phenol. 247
Figure 3.36. EDX mapping images of the catalysts as-synthesized. 248
Figure 3.37. EDX mapping images of the catalysts post the 1st recycle runs to degrade phenol.[이미지참조] 249
Figure 3.38. EDX mapping images of the catalysts post the 2nd recycle runs to degrade phenol.[이미지참조] 250
Figure 3.39. EDX mapping images of the catalysts post the 3rd recycle runs to degrade phenol.[이미지참조] 251
Figure 3.40. Illustration of ˙OH-mediated phenol degradation pathways, where the intermediates shown with m/z values were identified using LC-MS technique in negative mode, whereas m and z... 254
Figure 3.41. Schematic illustration for H₂O₂ homolysis on zirconium oxides supported by functional carbons. 256
Figure 4.1. Initial phenol degradation pathways via ˙OH/Cl˙ addition to phenol (A-B), H˙ abstraction from phenol (A-B), and electron (e⁻) transfer from phenol to ˙OH/Cl˙ (A-B). In (A-B), * and ** indicate dihydroxy-cyclohexadienyl and phenoxyl radicals, respectively. Two... 260
Figure 4.2. ¹H-NMR spectra of 3-chloro-4-methylbenzoic acid (A) and 2-chlorobenzene-1,4-dicarboxylic acid (B) dissolved in aqueous HF. In (A-B), peaks marked with * denote dimethyl... 280
Figure 4.3. XRD patterns of UiO-66 (A) and UiO-66-Cl (B) post being subjected to SC-CO₂ extraction (prior to the 1st cycle) and phenol degradation recycle runs (post the 1st, 2nd, and 3rd cycles)....[이미지참조] 282
Figure 4.4. HRTEM images of UiO-66 (A) and UiO-66-Cl (B). Illustration of a Zr oxo-cluster ((Zr)₆(μ₃₋O)₄(μ₃₋OH)₄) coordinated to twelve BDC (or BDC-Cl) struts in UiO-66 (or UiO-66-Cl),... 283
Figure 4.5. SEM images of UiO-66 (A) and UiO-66-Cl (B) and their particle size distributions (UiO-66 for (C); UiO-66-Cl for (D); number of particles counted~100). In (C-D), dPARTICLE indicates...[이미지참조] 284
Figure 4.6. N₂ isotherms of UiO-66 (A) and UiO-66-Cl (B) and their pore size (dPORE) distributions assessed via NLDFT technique (UiO-66 for (C); UiO-66-Cl for (D)).[이미지참조] 287
Figure 4.7. (A) Illustration of benzene-1,4-dicarboxylate (BDC), 2-chlorobenzene-1,4- dicarboxylate (BDC-Cl), and N,N'-dimethyl formamide (DMF) used to build UiO-66/UiO-66-Cl... 289
Figure 4.8. Titration curves of UiO-66 (the 2nd trial for (A); the 3rd trial for (C)) and UiO-66-Cl (the 2nd trial for (B); the 3rd trial for (D)), for which HCl was initially implemented to adjust pH values...[이미지참조] 293
Figure 4.9. Background-subtracted, in situ NH₃-DRIFT spectra of UiO-66 (A) and UiO-66-Cl (B) collected at 150 °C. The background signals were collected under a N₂ at 150 °C after the UiO-... 296
Figure 4.10. H₂O adsorption isotherms of UiO-66 and UiO-66-Cl collected at 20-40 °C (20 °C for (A-B); 30 °C for (C-D); 40 °C for (E-F)), where P/P₀ ranges are 0-1.0 for 20 °C, 0-0.80 for 30 °C,... 298
Figure 4.11. XP spectra of UiO-66 and UiO-66-Cl in the Zr 3d (A) and C 1s domains (B). In (A-B), gray dashed lines, gray empty circles, and black empty circles denote raw XP spectra, fitted XP... 301
Figure 4.12. XP spectra of UiO-66 and UiO-66-Cl in the O 1s (A), N 1s (B), and Cl 2p domains (C). In (A-C), gray dashed lines, gray empty circles, and black empty circles denote raw XP spectra,... 302
Figure 4.13. CO₂ adsorption isotherms of UiO-66 (A) and UiO-66-Cl (B) collected at -20-20 °C with P/P₀ range of 0-1.0. In (A-B), CO₂ adsorption isotherms were fitted using Toth equation and... 307
Figure 4.14. CO adsorption isotherms of UiO-66 (A) and UiO-66-Cl (B) collected at -20-20 °C with P/P₀ range of 0-1.0. In (A-B), CO adsorption isotherms were fitted using Toth equation and... 309
Figure 4.15. (A) Fittings of background-subtracted reaction data to pseudo-1st-order kinetic model (-ln (CH₂O₂ /CH₂O₂, ₀) versus time) to assess apparent reaction rate constants (kAPP values in Table...[이미지참조] 315
Figure 4.16. Proposed transition pathways of 5,5-dimethyl-1-pyrroline N-oxide (DMPO; spin trapper) to DMPO-OH/DMPO-OOH (A), DMPO-OH/DMPO-OOH to DMPO-X (B), and DMPO-OH to HDMPO-OH (D) along with the recovery of OH⁻ post its interaction with... 319
Figure 4.17. EPR spectra of reaction solutions collected via filtration of reaction mixtures containing H₂O₂, 5,5-dimethyl-1-pyrroline N-oxide (DMPO; spin trapper), UiO-66 (A), or UiO-66-... 321
Figure 4.18. EPR spectra of reaction solutions collected via filtration of reaction mixtures containing H₂O₂, 5,5-dimethyl-1-pyrroline N-oxide (DMPO; spin trapper), UiO-66 (A), or UiO-66-... 324
Figure 4.19. Molar concentration of phenol consumed (C*PHENOL) versus time in the absence (blank for (A)) or presence of UiO-66 (B)/UiO-66-Cl (C), for which UiO-66 (or UiO-66-Cl) was...[이미지참조] 331
Figure 4.20. (A) Background-subtracted, initial phenol degradation rates of UiO-66/UiO-66-Cl in a per-LA site basis (-rPHENOL, ₀, LA) with the alteration of catalyst particle diameters (dPARTICLE; size)...[이미지참조] 333
Figure 4.21. Fittings of background-subtracted reaction data to pseudo-1st-order kinetic model (-ln (CPHENOL/CPHENOL, ₀) versus time) for assessing apparent reaction rate constants (kAPP values in Table...[이미지참조] 334
Figure 4.22. Representation of phenol degradation pathways on UiO-66, where the intermediates shown with m/z values were identified using LC-MS technique in negative mode, whereas m and z... 336
Figure 4.23. Representation of phenol degradation pathways on UiO-66-Cl, where the intermediates shown with m/z values were identified using LC-MS technique in negative mode,... 337
Figure 4.24. Fittings of background-subtracted reaction data to pseudo-1st-order kinetic model (-ln (CPHENOL/CPHENOL, ₀) versus time) for assessing apparent reaction rate constants (kAPP values in Table...[이미지참조] 340
Figure 4.25. Fittings of background-subtracted reaction data to pseudo-1st-order kinetic model (-ln (CPOL/CPOL, ₀) versus time) to assess apparent reaction rate constants (kAPP values in Table 4.11) of...[이미지참조] 341
Figure 4.26. Plots of the logarithmic background-subtracted, initial phenol degradation rates of UiO-66/UiO-66-Cl in a per-LA site basis (-rPHENOL, ₀, LA for (A)) or in a per-BA site basis (-rPHENOL, ₀,...[이미지참조] 345
Figure 4.27. Fittings of background-subtracted reaction data to pseudo-1st-order kinetic model (-ln (CPHENOL/CPHENOL, ₀) versus time) for assessing apparent reaction rate constants (kAPP values in Table...[이미지참조] 346
Figure 4.28. Fittings of background-subtracted reaction data to pseudo-1st-order kinetic model (-ln (CPHENOL/CPHENOL, ₀) versus time) for assessing apparent reaction rate constants (kAPP values in Table...[이미지참조] 348
Figure 4.29. MOF architectures simplified for DFT calculations, where R denotes H (for UiO-66) or ClSUP/Cl⁻SUP/Cl˙SUP (for UiO-66-Cl).[이미지참조] 351
Figure 4.30. SEM (A, F, J, and N) and EDX mapping images of UiO-66 prior to or post phenol degradation recycle runs (B-E for prior to the 1st cycle; G-I for post the 1st cycle; K-M for post the 2nd...[이미지참조] 354
Figure 4.31. SEM (A, G, L, and Q) and EDX mapping images of UiO-66-Cl prior to or post phenol degradation recycle runs (B-F for prior to the 1st cycle; H-K for post the 1st cycle; M-P for post...[이미지참조] 355
Figure 4.32. (A) Background-subtracted, initial phenol degradation rates of UiO-66, UiO-66-Cl, Mn oxide-N, and Fe oxide-S in a per-LA site basis (-r'PHENOL, ₀, LA). In (A), the -r'PHENOL, ₀, LA values...[이미지참조] 357
Figure 4.33. Fittings of background-subtracted reaction data to pseudo-1st-order kinetic model (-ln (CPHENOL/CPHENOL, ₀) versus time) for assessing apparent reaction rate constants (kAPP values in Table...[이미지참조] 358
Figure 4.34. Fittings of background-subtracted reaction data to pseudo-1st-order kinetic model (-ln (Cxxx/Cxxx, ₀) versus time; XXX denotes acetaminophen (A), aniline (B), sulfanilamide (C), or...[이미지참조] 360
Figure 4.35. Schematic illustration for H₂O₂ homolysis for ˙OH-mediated Cl˙ evolution on functional UiO-66. 363