Title

Electrochemical Water Oxidation and Nitrogen Reduction Reaction Using Single-Layer Graphene-Coated Transition Metal Nanocatalysts

Alternative Title

차세대 에너지 생산을 위한 단층 그래핀 코팅 금속 나노촉매

DGIST Authors

Gisang Park ; Jong-Sung Yu ; Jongmin Choi

Advisor

유종성

Co-Advisor(s)

Jongmin Choi

Issued Date

2023

Awarded Date

2023-08-01

Citation

Gisang Park. (2023). Electrochemical Water Oxidation and Nitrogen Reduction Reaction Using Single-Layer Graphene-Coated Transition Metal Nanocatalysts. doi: 10.22677/THESIS.200000684465

Type

Thesis

Description

Single-layer graphene; metal nanoparticle; carbon defect; oxygen evolution reaction; nitrogen reduction reaction; ammonia

Table Of Contents

Abstract i
List of contents ii
List of tables iv
List of figures v

I. First chapter: Controllable synthesis of single-layer graphene over cobalt nanoparticles and insight into active sites for efficient oxygen evolution 1
1.1 Introduction 1
1.2 Experimental Section 3
1.2.1 Materials 3
1.2.2 Prepartion of SiO2 spheres 4
1.2.3 Preparation of cobalt silicate (Co2SiO4) 4
1.2.4 Preparation of Co@SG 4
1.2.5 Preparation of Co@N-SG 5
1.2.6 Preparation of Co@MG 5
1.2.7 Preparation of Co NPs 5
1.2.8 Preparation of defect-free Co@SG and hollow SG and N-SG cages 6
1.2.9 Electrode preparation on glassy carbon and Ni foam 6
1.3 Results and discussion 7
1.3.1 Preparation and Characterization 7
1.3.2 Electrochemical OER Performance 18
1.3.3 OER Mechanism 23
1.3.4 Magnet-Assisted Binder-Free Electrode for Efficient OER 25
1.3.5 Contribution to Catalytic Activity 28
1.3.6 The effect of carbon vacancies 33
1.3.7 Density Functional Theory (DFT) Calculations 34
1.4 Conclusion 40

II. Second chapter: The Influence of Graphene Overlayer on Nickel for Selective Nitrogen Electroreduction to Ammonia 42
2.1 Introduction 42
2.2 Experimental section 45
2.2.1 Material 45
2.2.2 Material characterization 45
2.2.3 Electrochemical measurement 45
2.2.4 Determination of ammonia yield and Faradaic efficiency 46
2.2.5 Detection of hydrazine in the electrolyte 47
2.3 Results and discussions 48
2.3.1 Preparation of Ni@SG, Ni@MG, and DF Ni@SG NPs 48
2.3.2 Preparation of the graphene-coated Ni foam electrodes 49
2.3.3 Preparation of GDL electrodes for NRR 50
2.3.4 Electrochemical NRR 51
2.3.5 Parasitic oxygen reduction reaction during NRR 55
2.3.6 XPS analyses 58
2.4 Conclusion 60

III. References 62
3.1 Reference for the first chapter 62
3.2 Reference for the second chapter 67

IV. Abstract (국문요약) 70

URI

http://hdl.handle.net/20.500.11750/46399
http://dgist.dcollection.net/common/orgView/200000684465

DOI

10.22677/THESIS.200000684465

Degree

Doctor

Department

Department of Energy Science and Engineering

Publisher

DGIST

Show Full Item Record