NiCo-LDH/Ti3C2 MXene hybrid materials for lithium ion battery with high-rate capability and long cycle life

Abstract

Nickel/cobalt-layered double hydroxides (NiCo-LDH) have been attracted increasing interest in the applications of anode materials for lithium ion battery (LIB), but the low cycle stability and rate performance are still limited its practice applications. To achieve high performance LIB, the surface-confined strategy has been applied to design and fabricate a new anode material of NiCo-LDH nanosheet anchored on the surface of Ti 3 C 2 MXene (NiCo-LDH/Ti 3 C 2 ). The ultra-thin, bended and wrinkled α-phase crystal with an interlayer spacing of 8.1 Å can arrange on the conductive substrates Ti 3 C 2 MXene directly, resulting in high electrolyte diffusion ability and low internal resistance. Furthermore, chemical bond interactions between the highly conductive Ti 3 C 2 MXene and NiCo-LDH nanosheets can greatly increase the ion and electron transport and reduce the volume expansion of NiCo-LDH during Li ion intercalation. As expected, the discharge capacity of 562 mAh g −1 at 5.0 A g −1 for 800 cycles without degradation can be achieved, rate capability and cycle performance are better than that of NiCo-LDH (~100 mAh g −1 ). Furthermore, the density function theory (DFT) calculations were performed to demonstrate that NiCo-LDH/Ti 3 C 2 system can be used as a highly desirable and promising anode material for lithium ion battery. NiCo-LDH/Ti 3 C 2 MXene hybrid materials were synthesized by electrostatic attraction strategy. This structure effectively promotes ion diffusion, alleviates the volume expansion for lithium ion battery anode with high-rate capability and long cycle life.