Development and Evaluation of TiO₂-based Catalysts for Photocatalytic CO₂ Reduction
- Title
- Development and Evaluation of TiO₂-based Catalysts for Photocatalytic CO₂ Reduction
- Alternative Title
- TiO2 기반 광촉매를 이용한 CO2 환원 촉매의 개발
- Author(s)
- Hiragond Chaitanya Balappa
- DGIST Authors
- Hiragond Chaitanya Balappa ; Su-Il In ; Jiwoong Yang
- Advisor
- 인수일
- Co-Advisor(s)
- Jiwoong Yang
- Issued Date
- 2022
- Awarded Date
- 2022/08
- Type
- Thesis
- Description
- Photocatalysis,CO2 reduction, solar fuels, TiO2, Pt NPs, Ag NPs, MoSe2
- Abstract
- Table Of Contents
-
Chapter I Introduction 1
1.1 CO2 emissions 1
1.1.1 Greenhouse gases and the Global warming effect 1
1.2 Research and development strategies for CO2 normalization 3
1.2.1 CO2 disposal 3
1.2.2 CO2 capture and storage 4
1.2.3 CO2 reduction 4
1.3 Strategies for CO2 reduction 5
1.3.1 Thermal CO2 reduction 5
1.3.2 Biocatalytic CO2 reduction 6
1.3.3 Electrocatalytic CO2 conversion 6
1.4 Photocatalytic CO2 reduction 7
1.4.1 Fundamentals of CO2 photoreduction 8
1.4.2 Existing CO2 reduction pathways 10
1.5 Factors affecting the photocatalytic CO2 reduction 11
1.5.1 Light absorption ability of semiconductor 11
1.5.2 Charge separation 12
1.5.3 CO2 adsorption and activation 13
1.5.4 Role of H2O 13
1.5.5 Reaction type (gas or liquid phase 14
1.5.6 Reactor type (batch or flow reactor 15
1.5.7 Others 15
1.6 Challenges of photocatalytic CO2 reduction 16
1.7 Titanium dioxide (TiO2) as a photocatalyst 16
1.8 Stretergies for TiO2 modifications 17
1.8.1 Non-metal doping 17
1.8.2 Metal doping 18
1.8.3 Metal-semiconductor coupling 19
1.8.4 Heterostructure formation 20
1.8.5 Surface modification of TiO2 21
1.9 Research approaches and organization of Thesis 21
1.10 References 23
Chapter II Characterization and analysis tools 32
2.1. X-ray diffraction (XRD) 32
2.2 Raman spectroscopy 33
2.3 High-resolution transmission electron microscopy (HR-TEM) 33
2.4 Energy-dispersive X-ray spectroscopy (EDS or EDX or EDAX) 34
2.5 X-ray photoelectron spectroscopy (XPS) 35
2.6 X-ray absorption spectroscopy (XAS) 36
2.7 Ultraviolet-Visible diffuse reflectance spectroscopy (UV-Vis DRS) 38
2.8 Photoluminescence (PL) spectroscopy 39
2.9 Time-resolved photoluminescence (TRPL) spectroscopy 40
2.10 Brunaue-Emmet-Teller (BET) 40
2.11 CO2-Temperature Program Desorption (TPD) 41
2.12 Diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) 41
2.13 Gas Chromatography (GC) 42
2.14 Gas Chromatography-Mass Spectrometry (GC-MS) 44
2.15 Photocatalytic CO2 reduction set-up 45
2.16 References 47
Chapter III Pt deposited N-doped graphene oxide enfolded reduced titania for highly stable and selective gas-phase photocatalytic CO2 reduction into CH4 49
3.1 Introduction 49
3.2 Experimental section 50
3.2.1 Synthesis of Reduced Titania 50
3.2.2 Synthesis of N-doped GO-RT (NGO-RT) composite 51
3.2.3 Synthesis of Pt deposited NGO-RT composite (Pt-NGO-RT) 51
3.2.4 Material characterization 51
3.2.5 Photocatalytic tests 52
3.2.6 Coumarin dye test 53
3.3 Results and discussion 53
3.4 Photocatalytic CO2 reduction to CH4 58
3.4.1 Selectivity and stability of catalytic reaction 60
3.4.2 Band potentials and reaction pathways 62
3.5 Discussion on the mechanism of CO2 reduction 63
3.6 Conclusions 65
3.7 References 69
Chapter IV Surface modified Ag@Ru-P25 for photocatalytic CO2 conversion with high selectivity over CH4 formation at the solid-gas interface 77
4.1 Introduction 77
4.2 Experimental section 78
4.2.1 Synthesis of Ru doped P25 (Ru-P25) 78
4.2.2 Synthesis of H2O2 treated Ag deposited Ru-P25 (Ag@Ru-P25) 79
4.2.3 Characterization 79
4.2.4 Photocatalytic CO2 reduction 80
4.2.5 Coumarin dye test 81
4.2.6 Isotopic test 81
4.2.7 Electrochemical analysis 81
4.2.8 In-situ DRIFTS analysis 81
4.3 Results and discussion 81
4.3.1 Synthesis and characterization 81
4.3.2 Photocatalytic CO2 reduction 86
4.3.3 Optical properties, band structure, and charge separation 89
4.3.4 Effect of H2O2 93
4.4 Mechanism of CO2 photoreduction 95
4.5 Conclusions 98
4.6 References 103
Chapter V Photocatalytic CO2 reduction into CH4 using Pt-TiO2-MoSe2 hybrid composite: dual cocatalysts and photonic effect to enrich the catalysis 109
5.1 Introduction 109
5.2 Experimental section 111
5.2.1 Exfoliation of MoSe2 111
5.2.2 Synthesis of P25-MoSe2 (TM) 111
5.2.3 Synthesis of Pt deposited P25-MoSe2 (Pt-TM) 111
5.2.4 Characterization 111
5.2.5 Photocatalytic CO2 reduction 112
5.2.6 Coumarin dye test 113
5.2.7 Electrochemical analysis 113
5.3 Results and discussion 113
5.3.1 Synthesis and characterization 113
5.3.2 Photocatalytic CO2 reduction 119
5.3.2 Surface properties and mechanism of CO2 reduction 120
5.4 Conclusions 125
5.5 References 127
Chapter VI Summary 133
Abstract in Korean 136
- URI
-
http://dgist.dcollection.net/common/orgView/200000630369
http://hdl.handle.net/20.500.11750/16799
- Degree
- Doctor
- Department
- Department of Energy Science and Engineering
- Publisher
- DGIST
- Related Researcher
-
-
In, Su-Il
- Research Interests CO2 conversion to hydrocarbon fuels; Water splitting for hydrogen generation; Quantum dot devices; Dye sensitized solar cells; Environmental remediation; Synthesis of functional nanomaterials; CO2 연료전환; 수소생산을 위한 광전기화학적 물분해; 양자점 태양전지; 염료감응 태양전지; 공해물질 저감연구; 기능성 나노소재 개발
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