Title

Synthetic Preparation of Transition Metal Compound Composites for High-Performance Lithium-Sulfur Batteries

DGIST Authors

Yu Bo ; Jiwoong Yang ; Jong-Sung Yu

Advisor

양지웅

Co-Advisor(s)

Jong-Sung Yu

Issued Date

2026

Awarded Date

2026-02-01

Type

Thesis

Description

lithium–sulfur batteries, NiCoO2–(Ni,Co)Se2 nanorods, titanium monoxide, N-doped graphitized porous carbon, polysulfides adsorption and catalytic conversion.

Table Of Contents

ABSTRACT i
List of Contents iv

Chapter 1. Background 1
1.1 Global energy challenges 1
1.2 Lithium-sulfur batteries: overview and promise 1
1.3 Major challenges in lithium-sulfur battery development 2
1.4 Strategies for performance enhancement 4
1.5 Role of transition metal compound composites 5
1.6 Design principles 6
1.7 Research progress and representative approaches 7
1.8 Outlook and significance 8
1.9 Summary 8
1.10 References 9
Chapter 2: Construction of NiCoO2-(Ni,Co)Se2 hybrid nanorods as an effective bifunctional interlayer for lithium-sulfur batteries 10
2.1 Introduction 10
2.2. Experimental sections 11
2.2.1 Materials 11
2.2.2 Synthesis of NiCo composite 12
2.2.3 Synthesis of NiCoO2-(Ni,Co)Se2 hybrid nanorods 12
2.2.4 Construction of PP separator coated NiCoO2-(Ni,Co)Se2 hybrid nanorods 13
2.2.5 Preparation of S cathode 13
2.2.6 Adsorption test of LiPSs 14
2.2.7 Assembly of Li2S6 symmetric cells 14
2.2.8 Li+ diffusion coefficient of the Li-S full cell with NCOSe/PP separator 14
2.2.9 Contact angle test between different separators and the electrolyte 14
2.2.10 Diffusion of Li2S6 solution in H-type cell with different separators 15
2.2.11 Materials characterization 15
2.2.12 Battery assembly and electrochemical measurements 16
2.3 Results and discussions 16
2.4 Conclusions 34
2.5 References 34
Chapter 3. Magnesiothermically Synthesized TiO-decorated 3D N-doped Graphitized Porous Carbon for Li–S Batteries: Enhanced Conductivity, Polysulfides Trapping and Accelerated Redox Kinetics 41
3.1 Introduction 41
3.2. Experimental section 43
3.2.1 Reagents and materials 43
3.2.2 Materials characterization 43
3.2.3 Density functional theory calculations methods 44
3.2.4 Synthesis of TiO-decorated 3D N-doped graphitized porous carbon 45
3.2.5 Preparation of sulfur cathode 46
3.2.6 Adsorption test of LiPSs 47
3.2.7 Assembly of Li2S6 symmetric cells 47
3.2.8 The precipitation test of Li2S 47
3.2.9 Li+ diffusion coefficient 48
3.2.10 Coin cell assembly and electrochemical measurements 48
3.2.11 In-situ XRD analysis test 49
3.2.12 Pouch cell assembly and performance evaluation 49
3.3 Results and discussions 50
3.3.1 Fabrication of TiO-NGPC/S 50
3.3.2 Characterization of the TiO-NGPC 50
3.3.3 Electrochemical characterization of Li–S full cell with the TiO-NGPC/S 64
3.3.4 Characterization of the adsorption and catalytic performance mechanism of the TiO-NGPC 70
3.3.5 Characterization of In-situ XRD and performance of pouch cell 77
3.4 Conclusions 79
3.5 References 80
요 약 문 88

URI

https://scholar.dgist.ac.kr/handle/20.500.11750/59621
http://dgist.dcollection.net/common/orgView/200000942693

DOI

10.22677/THESIS.200000942693

Degree

Doctor

Department

Department of Energy Science and Engineering

Publisher

DGIST

Show Full Item Record