Formation of a Surficial Bifunctional Nanolayer on Nb2O5for Ultrastable Electrodes for Lithium-Ion Battery.
Safe and long cycle life electrode materials for lithium-ion batteries are significantly important to meet the increasing demands of rechargeable batteries. Niobium pentoxide (Nb2O5) is one of the highly promising candidates for stable electrodes due to its safety and minimal volume expansion. Nevertheless, pulverization and low conductivity of Nb2O5have remained as inherent challenges for its practical use as viable electrodes. A highly facile method is proposed to improve the overall cycle retention of Nb2O5microparticles by ammonia (NH3) gas-driven nitridation. After nitridation, an ultrathin surficial layer (2 nm) is formed on the Nb2O5, acting as a bifunctional nanolayer that allows facile lithium (Li)-ion transport (10-100 times higher Li diffusivity compared with pristine Nb2O5microparticles) and further prevents the pulverization of Nb2O5. With the subsequent decoration of silver (Ag) nanoparticles (NPs), the low electric conductivity of nitridated Nb2O5is also significantly improved. Cycle retention is greatly improved for nitridated Nb2O5(96.7%) compared with Nb2O5(64.7%) for 500 cycles. Ag-decorated, nitridated Nb2O5microparticles and nitridated Nb2O5microparticles exhibit ultrastable cycling for 3000 cycles at high current density (3000 mA g-1), which highlights the importance of the surficial nanolayer in improving overall electrochemical performances, in addition to conductive NPs.
Department of Materials Science and Engineering, Korea Advanced Institute of Science and Technology, 291 Daehak-Ro, Yuseong-Gu, Daejeon, 305-701, Republic of Korea.
Jun Young
JY
Cheong
Department of Materials Science and Engineering, Korea Advanced Institute of Science and Technology, 291 Daehak-Ro, Yuseong-Gu, Daejeon, 305-701, Republic of Korea.
Chanhoon
C
Kim
Department of Materials Science and Engineering, Korea Advanced Institute of Science and Technology, 291 Daehak-Ro, Yuseong-Gu, Daejeon, 305-701, Republic of Korea.
Ji-Won
JW
Jung
Department of Materials Science and Engineering, Korea Advanced Institute of Science and Technology, 291 Daehak-Ro, Yuseong-Gu, Daejeon, 305-701, Republic of Korea.
Ki Ro
KR
Yoon
Department of Materials Science and Engineering, Korea Advanced Institute of Science and Technology, 291 Daehak-Ro, Yuseong-Gu, Daejeon, 305-701, Republic of Korea.
Su-Ho
SH
Cho
Department of Materials Science and Engineering, Korea Advanced Institute of Science and Technology, 291 Daehak-Ro, Yuseong-Gu, Daejeon, 305-701, Republic of Korea.
Doo-Young
DY
Youn
Department of Materials Science and Engineering, Korea Advanced Institute of Science and Technology, 291 Daehak-Ro, Yuseong-Gu, Daejeon, 305-701, Republic of Korea.
Hye-Yeon
HY
Jang
Department of Materials Science and Engineering, Korea Advanced Institute of Science and Technology, 291 Daehak-Ro, Yuseong-Gu, Daejeon, 305-701, Republic of Korea.
Il-Doo
ID
Kim
Nb2O5; electrodes; lithium; nitridation; surficial bifunctional nanolayers