TY - JOUR
T1 - Composite Polymer Electrolytes with Li7La3Zr2O12 Garnet-Type Nanowires as Ceramic Fillers
T2 - Mechanism of Conductivity Enhancement and Role of Doping and Morphology
AU - Yang, Ting
AU - Zheng, Jin
AU - Cheng, Qian
AU - Hu, Yan Yan
AU - Chan, Candace
PY - 2017/7/5
Y1 - 2017/7/5
N2 - Composite polymer solid electrolytes (CPEs) containing ceramic fillers embedded inside a polymer-salt matrix show great improvements in Li+ ionic conductivity compared to the polymer electrolyte alone. Lithium lanthanum zirconate (Li7La3Zr2O12, LLZO) with a garnet-type crystal structure is a promising solid Li+ conductor. We show that by incorporating only 5 wt % of the ceramic filler comprising undoped, cubic-phase LLZO nanowires prepared by electrospinning, the room temperature ionic conductivity of a polyacrylonitrile-LiClO4-based composite is increased 3 orders of magnitude to 1.31 × 10-4 S/cm. Al-doped and Ta-doped LLZO nanowires are also synthesized and utilized as fillers, but the conductivity enhancement is similar as for the undoped LLZO nanowires. Solid-state nuclear magnetic resonance (NMR) studies show that LLZO NWs partially modify the PAN polymer matrix and create preferential pathways for Li+ conduction through the modified polymer regions. CPEs with LLZO nanoparticles and Al2O3 nanowire fillers are also studied to elucidate the role of filler type (active vs passive), LLZO composition (undoped vs doped), and morphology (nanowire vs nanoparticle) on the CPE conductivity. It is demonstrated that both intrinsic Li+ conductivity and nanowire morphology are needed for optimal performance when using 5 wt % of the ceramic filler in the CPE.
AB - Composite polymer solid electrolytes (CPEs) containing ceramic fillers embedded inside a polymer-salt matrix show great improvements in Li+ ionic conductivity compared to the polymer electrolyte alone. Lithium lanthanum zirconate (Li7La3Zr2O12, LLZO) with a garnet-type crystal structure is a promising solid Li+ conductor. We show that by incorporating only 5 wt % of the ceramic filler comprising undoped, cubic-phase LLZO nanowires prepared by electrospinning, the room temperature ionic conductivity of a polyacrylonitrile-LiClO4-based composite is increased 3 orders of magnitude to 1.31 × 10-4 S/cm. Al-doped and Ta-doped LLZO nanowires are also synthesized and utilized as fillers, but the conductivity enhancement is similar as for the undoped LLZO nanowires. Solid-state nuclear magnetic resonance (NMR) studies show that LLZO NWs partially modify the PAN polymer matrix and create preferential pathways for Li+ conduction through the modified polymer regions. CPEs with LLZO nanoparticles and Al2O3 nanowire fillers are also studied to elucidate the role of filler type (active vs passive), LLZO composition (undoped vs doped), and morphology (nanowire vs nanoparticle) on the CPE conductivity. It is demonstrated that both intrinsic Li+ conductivity and nanowire morphology are needed for optimal performance when using 5 wt % of the ceramic filler in the CPE.
KW - composite polymer electrolyte
KW - electrospinning
KW - garnet-type solid electrolyte
KW - nanowires
KW - NMR
KW - polyacrylonitrile
UR - http://www.scopus.com/inward/record.url?scp=85022061232&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85022061232&partnerID=8YFLogxK
U2 - 10.1021/acsami.7b03806
DO - 10.1021/acsami.7b03806
M3 - Article
C2 - 28598143
AN - SCOPUS:85022061232
VL - 9
SP - 21773
EP - 21780
JO - ACS applied materials & interfaces
JF - ACS applied materials & interfaces
SN - 1944-8244
IS - 26
ER -