Porous TiNb24O62microspheres as high-performance anode materials for lithium-ion batteries of electric vehicles.
TiNb24O62is explored as a new anode material for lithium-ion batteries. Microsized TiNb24O62particles (M-TiNb24O62) are fabricated through a simple solid-state reaction method and porous TiNb24O62microspheres (P-TiNb24O62) are synthesized through a facile solvothermal method for the first time. TiNb24O62exhibits a Wadsley-Roth shear structure with a structural unit composed of a 3 × 4 octahedron-block and a 0.5 tetrahedron at the block-corner. P-TiNb24O62with an average sphere size of ∼2 μm is constructed by nanoparticles with an average size of ∼100 nm, forming inter-particle pores with a size of ∼8 nm and inter-sphere pores with a size of ∼55 nm. Such desirable porous microspheres are an ideal architecture for enhancing the electrochemical performances by shortening the transport distance of electrons/Li+-ions and increasing the reaction area. Consequently, P-TiNb24O62presents outstanding electrochemical performances in terms of specific capacity, rate capability and cyclic stability. The reversible capacities of P-TiNb24O62are, respectively, as large as 296, 277, 261, 245, 222, 202 and 181 mA h g-1at 0.1, 0.5, 1, 2, 5, 10 and 20 C, which are obviously larger than those of M-TiNb24O62(258, 226, 210, 191, 166, 147 and 121 mA h g-1). At 10 C, the capacity of P-TiNb24O62still remains at 183 mA h g-1over 500 cycles with a decay of only 0.02% per cycle, whereas the corresponding values of M-TiNb24O62are 119 mA h g-1and 0.04%. These impressive results indicate that P-TiNb24O62can be a promising anode material for lithium-ion batteries of electric vehicles.
State Key Laboratory of Marine Resource Utilization in South China Sea, College of Materials and Chemical Engineering, Hainan University, Haikou 570228, Hainan, PR China. linchunfu@hainu.edu.cn.
Chao
C
Yang
State Key Laboratory of Marine Resource Utilization in South China Sea, College of Materials and Chemical Engineering, Hainan University, Haikou 570228, Hainan, PR China. linchunfu@hainu.edu.cn.
Shengjue
S
Deng
State Key Laboratory of Marine Resource Utilization in South China Sea, College of Materials and Chemical Engineering, Hainan University, Haikou 570228, Hainan, PR China. linchunfu@hainu.edu.cn.
Chunfu
http://orcid.org/0000-0003-0251-7938
C
Lin
State Key Laboratory of Marine Resource Utilization in South China Sea, College of Materials and Chemical Engineering, Hainan University, Haikou 570228, Hainan, PR China. linchunfu@hainu.edu.cn.
Shiwei
S
Lin
State Key Laboratory of Marine Resource Utilization in South China Sea, College of Materials and Chemical Engineering, Hainan University, Haikou 570228, Hainan, PR China. linchunfu@hainu.edu.cn.
Yongjun
Y
Chen
State Key Laboratory of Marine Resource Utilization in South China Sea, College of Materials and Chemical Engineering, Hainan University, Haikou 570228, Hainan, PR China. linchunfu@hainu.edu.cn.
Jianbao
J
Li
State Key Laboratory of New Ceramics and Fine Processing, School of Materials Science and Engineering, Tsinghua University, Beijing 100084, PR China.
Hui
H
Wu