TY - JOUR
T1 - Enhanced Proton Conductivity of Sulfonated Polysulfone Membranes under Low Humidity via the Incorporation of Multifunctional Graphene Oxide
AU - Li, Jinzhao
AU - Wu, Hong
AU - Cao, Li
AU - He, Xueyi
AU - Shi, Benbing
AU - Li, Yan
AU - Xu, Mingzhao
AU - Jiang, Zhongyi
N1 - Generated from Scopus record by KAUST IRTS on 2023-09-21
PY - 2019/8/23
Y1 - 2019/8/23
N2 - Development of proton exchange membranes with sufficiently high proton conductivity, especially at low relative humidity (RH), remains a big challenge in the field of fuel cells. In this study, graphene oxide-based nanoscale ionic materials (NIMs-GO) were prepared by sulfonation with 3-(trihydroxysilyl)-1-propanesulfonic acid and subsequent neutralization with amino-terminated polyoxypropylene (PO)-polyoxyethylene (EO) block copolymer. The resultant NIMs-GO with acid-base pairs and hygroscopic EO units were incorporated into sulfonated polysulfone (SPSF) to fabricate nanocomposite membranes. A matrix-softening phenomenon was found due to the extensive interaction between the SPSF matrix and the amphiphilic NIMs-GO, which primarily contributes to the homogeneous dispersion of the NIMs-GO filler in the nanocomposite membranes. The acid-base pairs and the interconnected hydrogen-bonded networks formed between the EO units and water molecules imparted efficient proton transfer via the Grotthuss mechanism. The water uptake and retention ability of the SPSF/NIMs-GO nanocomposite membranes were enhanced due to the hydrophilic EO units on NIMs-GO. As a result, the nanocomposite membrane exhibited a 52% increase compared with the pristine SPSF membrane in proton conductivity at 75 °C, 100% RH and a 24-fold increase at 75 °C, 40% RH. This enhanced proton conductivity led to an elevated fuel cell performance under both hydrous and low RH conditions.
AB - Development of proton exchange membranes with sufficiently high proton conductivity, especially at low relative humidity (RH), remains a big challenge in the field of fuel cells. In this study, graphene oxide-based nanoscale ionic materials (NIMs-GO) were prepared by sulfonation with 3-(trihydroxysilyl)-1-propanesulfonic acid and subsequent neutralization with amino-terminated polyoxypropylene (PO)-polyoxyethylene (EO) block copolymer. The resultant NIMs-GO with acid-base pairs and hygroscopic EO units were incorporated into sulfonated polysulfone (SPSF) to fabricate nanocomposite membranes. A matrix-softening phenomenon was found due to the extensive interaction between the SPSF matrix and the amphiphilic NIMs-GO, which primarily contributes to the homogeneous dispersion of the NIMs-GO filler in the nanocomposite membranes. The acid-base pairs and the interconnected hydrogen-bonded networks formed between the EO units and water molecules imparted efficient proton transfer via the Grotthuss mechanism. The water uptake and retention ability of the SPSF/NIMs-GO nanocomposite membranes were enhanced due to the hydrophilic EO units on NIMs-GO. As a result, the nanocomposite membrane exhibited a 52% increase compared with the pristine SPSF membrane in proton conductivity at 75 °C, 100% RH and a 24-fold increase at 75 °C, 40% RH. This enhanced proton conductivity led to an elevated fuel cell performance under both hydrous and low RH conditions.
UR - https://pubs.acs.org/doi/10.1021/acsanm.9b00446
UR - http://www.scopus.com/inward/record.url?scp=85078555868&partnerID=8YFLogxK
U2 - 10.1021/acsanm.9b00446
DO - 10.1021/acsanm.9b00446
M3 - Article
SN - 2574-0970
VL - 2
SP - 4734
EP - 4743
JO - ACS Applied Nano Materials
JF - ACS Applied Nano Materials
IS - 8
ER -