TY - JOUR
T1 - Molecular-level anchoring of polymer cathodes on carbon nanotubes towards rapid-rate and long-cycle sodium-ion storage
AU - Hu, Yuxiang
AU - Zhang, Kai
AU - Hu, Han
AU - Wang, Songcan
AU - Ye, Delai
AU - Monteiro, Michael J.
AU - Jia, Zhongfan
AU - Wang, Lianzhou
PY - 2018/7/10
Y1 - 2018/7/10
N2 - Nitroxide radical polymers (NRPs) have attracted increasing research interest as promising cathode materials for sodium ion batteries, primarily owing to their high-voltage (ca. 3.47 V vs. Na+/Na), environment compatibility, low-cost, and rich resources. However, such NRP cathodes are subjected to low rate-capacity and poor cycling stability because of their inferior conductivity and dissolubility in the electrolyte. Herein, we report a "molecular glue" strategy to anchor pyrene functionalized NRPs on a highly condutive carbon nanotube (CNT) matrix through π-π interactions between the pyrene functional groups and CNTs. As such, the NRP layer is homogeneously "glued" on the carbon substrates and the non-covalent interaction with CNTs drastically improves the insolubility and electric conductivity of the composite. Benefiting from these structural merits, the new nanocomposite exhibits a record cyclability (92% capacity retention at a high current density of 2.2 A g-1 after 6000 cycles) and remarkable rate capability (78 mA h g-1 at 5.5 A g-1) when evaluated as a high-voltage cathode material for SIBs. This work demonstrates the importance of rational hybridization of radical polymers and carbon substrates for enhanced electrochemical performance and provides insightful guides for designing high-performance polymer-based composites for energy storage applications.
AB - Nitroxide radical polymers (NRPs) have attracted increasing research interest as promising cathode materials for sodium ion batteries, primarily owing to their high-voltage (ca. 3.47 V vs. Na+/Na), environment compatibility, low-cost, and rich resources. However, such NRP cathodes are subjected to low rate-capacity and poor cycling stability because of their inferior conductivity and dissolubility in the electrolyte. Herein, we report a "molecular glue" strategy to anchor pyrene functionalized NRPs on a highly condutive carbon nanotube (CNT) matrix through π-π interactions between the pyrene functional groups and CNTs. As such, the NRP layer is homogeneously "glued" on the carbon substrates and the non-covalent interaction with CNTs drastically improves the insolubility and electric conductivity of the composite. Benefiting from these structural merits, the new nanocomposite exhibits a record cyclability (92% capacity retention at a high current density of 2.2 A g-1 after 6000 cycles) and remarkable rate capability (78 mA h g-1 at 5.5 A g-1) when evaluated as a high-voltage cathode material for SIBs. This work demonstrates the importance of rational hybridization of radical polymers and carbon substrates for enhanced electrochemical performance and provides insightful guides for designing high-performance polymer-based composites for energy storage applications.
KW - Nitroxide radical polymers (NRPs)
KW - polymer cathodes
KW - molecular-level
KW - rapid-rate and long-cycle sodium-ion storage
KW - molecular glue
UR - http://www.scopus.com/inward/record.url?scp=85054202239&partnerID=8YFLogxK
UR - http://purl.org/au-research/grants/arc/FT130101442
U2 - 10.1039/c8qm00163d
DO - 10.1039/c8qm00163d
M3 - Article
AN - SCOPUS:85054202239
VL - 2
SP - 1805
EP - 1810
JO - Materials Chemistry Frontiers
JF - Materials Chemistry Frontiers
SN - 2052-1537
IS - 10
ER -