Cited 0 time in webofscience Cited 0 time in scopus

Development of alternative electrolyte membranes for proton exchange membrane fuel cells

Title
Development of alternative electrolyte membranes for proton exchange membrane fuel cells
Translated Title
수소 이온 교환막 연료전지를 위한 대체 전해질 막 개발
Authors
Oh, Kwang jin
DGIST Authors
Oh, Kwang jin; Shanmugam, Sangaraju; Kim, Ha Suck
Advisor(s)
Shanmugam, Sangaraju
Co-Advisor(s)
Kim, Ha Suck
Issue Date
2016
Degree Date
2016. 2
Type
Thesis
Access Rights
The original item will not be provided upon request from the author
Keywords
Block copolymerPolymerizationPhase morphologyProton conductivityComposite membraneOxidative stability블록 공중합체수소이온 전도도복합막이온교환능산화적 안정도
Abstract
Sulfonated poly(arylene ether ketone) (SPAEK) block copolymers were synthesized through nucleophilic aromatic substitution polymerization. The prepared block copolymer and membrane were characterized with NMR, GPC, TEM, and TGA. Compared with a Nafi-on (NRE-212), state-of-the-art proton conducting membrane, the block copolymer mem-brane showed a well separated phase morphology and high proton conductivity under fully hydrated condition at 80 °C. The fuel cell operated with a SPAEK membrane showed a cur-rent density of 1617 mA cm-2 at 0.6 V under 100 % relative humidity (RH), whereas a NRE-212 membrane exhibited a current density of 1238 mA cm-2, which is about 30 % higher than newly prepared SPEAK membrane. In addition, the maximum power density of 1160, and 800 mW cm-2 was observed for SPAEK, NRE-212 membranes, respectively at 80 °C under 100 % RH condition. The SPAEK membrane exhibited 1.4-folds enhancement in the maxi-mum power density compared with the NRE-212 membrane. SPAEK mixed with polyoxo-metalate membrane was fabricated by using phosphotungstic acid and 3-aminopropyl-trioxomethlsilane hybrid with modified graphene oxide. The composite membrane showed better water uptake, ion exchange capacity, oxidative stability and proton conductivity. Un-der low RH condition (25 to 50 %), the fuel cell performance was much higher than pristine SPAEK membrane. At 80 °C under 50 % RH, the composite membrane showed a current density of 453 mA cm-2 at 0.6 V which is 1.4 times higher than the SPAEK membrane (324 mA cm-2). Under low potential (0.3 V), the current density of the SPAEK and composite membrane was 1112 mA cm-2 and 1995 mA cm-2, respectively. The current density of the composite membrane showed 1.8 times higher than the SPAEK membrane. Likewise, maxi-mum power density of the composite membrane was superior compared with the SPAEK membrane. ⓒ 2016 DGIST
Table Of Contents
1. INTRODUCTION 1 -- 1.1 Introduction 1 -- 1.2 Theoretical background 3 -- 1.2.1 Historical background 3 -- 1.2.2 Types of fuel cells 4 -- 1.3 Polymer electrolyte fuel cell 9 -- 1.3.1 Principle and component of PEMFC 9 -- 1.3.2 Reaction thermodynamics of fuel cell 11 -- 1.3.3 Performance of PEMFCs 12 -- 1.3.4 Membrane electrode assembly 15 -- 1.4 Polymer electrolyte membrane 15 -- 1.4.1 Types of polymer electrolyte membrane 15 -- 1.4.2 Characteristics of polymer electrolyte membrane 19 -- 1.4.3 Recent research trend 22 -- 2. EXPERIMENTAL METHODOLOGY 24 -- 2.1 Sulfonated poly(arylene ether ketone) block copolymer 24 -- 2.1.1 Materials 24 -- 2.1.2 Synthesis of sulfonated dihydroxybenzophenone 24 -- 2.1.3 Synthesis of hydrophilic oligomer 25 -- 2.1.4 Synthesis of hydrophobic oligomer 25 -- 2.1.5 Synthesis of block copolymer 26 -- 2.1.6 Preparation of membrane 26 -- 2.2 SPAEK / Phosphotungstic acid – modified graphene oxide composite membrane 27 -- 2.2.1 Materials 27 -- 2.2.2 Preparation of graphene oxide 27 -- 2.2.3 Preparation of reduced graphene oxide 28 -- 2.2.4 Preparation of modified graphene oxide 28 -- 2.2.5 Preparation of PW-mGO hybrid material 28 -- 2.2.6 Fabrication of SPAEK / PW-mGO composite membrane 30 -- 2.3 Measurements 31 -- 2.3.1 1H NMR spectra and gel permeation chromatography 31 -- 2.3.2 Water uptake and ion exchange capacity 31 -- 2.3.3 Oxidative stability test 32 -- 2.3.4 Transmission electron microscopic (TEM) observation 32 -- 2.3.5 Small angle X-ray scattering (SAXS) 33 -- 2.3.6 Fourier-transform infrared (FT-IR) spectra 33 -- 2.3.7 Proton conductivity 34 -- 2.3.8 Thermal gravimetric analyzer investigation 34 -- 2.3.9 Fuel cell performance evaluation 35 -- 3. RESULTS AND DISCUSSION 36 -- 3.1 SPAEK block copolymer membranes 36 -- 3.1.1 Characterization of SPAEK block copolymers 36 -- 3.1.2 Phase separation morphology of SPAEK membranes 41 -- 3.1.3 Proton conductivity and fuel cell performance 44 -- 3.1.4 Thermal stability 48 -- 3.1.5 Durability test 50 -- 3.2 SPAEK / PW-MGO composite membrane 51 -- 3.2.1 Characterization of PW-MGO 51 -- 3.2.2 Characterization of SPAEK / PW-mGO membrane 53 -- 3.2.3 Proton conductivity and fuel cell performance 56 -- 4. CONCLUSIONS 68 -- 5. REFERENCES 70
URI
http://dgist.dcollection.net/jsp/common/DcLoOrgPer.jsp?sItemId=000002227709
http://hdl.handle.net/20.500.11750/1447
DOI
10.22677/thesis.2227709
Degree
Master
Department
Energy Systems Engineering
University
DGIST
Files:
There are no files associated with this item.
Collection:
Energy Science and EngineeringThesesMaster


qrcode mendeley

Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.

BROWSE