MoO2/Mo2C/C spheres as anode materials for lithium ion batteries

Abstract

MoO2/Mo2C/C spheres have been synthesized through hydrothermal and calcination processes. MoO2 is well known for its high theoretical capacity of 838 mAh g-1, but undergoes capacity fading during Li+ insertion/extraction processes. Mo2C has high specific conductance (1.02 x 102 S cm-1) that can provide better electronic conductivity. Carbon is popular for its ability to accommodate the volume variation during charge/discharge. By taking advantage of the combination of Mo2C and C, these MoO2/Mo2C/C spheres demonstrate not only high cycling performance, but also good rate capability when they are used as anode materials for lithium ion batteries. After 100 cycles at 100 mA g-1, the discharge capacities of the MoO2/ Mo2C/C spheres remain at 800 mAh g-1, suggesting that MoO2/Mo2C/C spheres are promising candidates as anode material for lithium ion batteries. Disciplines Engineering | Physical Sciences and Mathematics Publication DetailsIhsan, M., Wang, H., Majid, S. R., Yang, J., Kennedy, S. J., Guo, Z. & Liu, H. Kun. (2016 AbstractMoO 2 /Mo 2 C/C spheres have been synthesized through hydrothermal and calcination processes. MoO 2 is well known for its high theoretical capacity of 838 mAh g -1 , but undergoes capacity fading during Li + insertion/extraction processes. Mo 2 C has high specific conductance (1.02 × 10 2 S cm -1 ) that can provide better electronic conductivity. Carbon is popular for its ability to accommodate the volume variation during charge/discharge. By taking advantage of the combination of Mo 2 C and C, these MoO 2 /Mo 2 C/C spheres demonstrate not only high cycling performance, but also good rate capability when they are used as anode materials for lithium ion batteries. After 100 cycles at 100 mA g -1 , the discharge capacities of the MoO 2 /Mo 2 C/C spheres remain at 800 mAh g -1 , suggesting that MoO 2 /Mo 2 C/C spheres are promising candidates as anode material for lithium ion batteries.

Mixed Molybdenum Oxides with Superior Performances as an Advanced Anode Material for Lithium-Ion Batteries

“…For MoO 2 , the first discharge capacity is only 670.5 mAh·g −1 while the capacity gradually increases upon cycling and attains 781.7 mAh·g −1 after 15 cycles. This activation process has been reported by other groups and may be attributed to the partial loss of crystallinity of the material during the cycling132829, accompanied with a larger fraction of the material undergoing further conversion reaction instead of stopping at Li x MoO 2 phase30. Nonetheless, a rapid capacity deterioration decay can be observed once the capacity reaches the maximum value and only a capacity of 325.7 mAh·g −1 remains after 50 cycles.…”

“…The conclusion that the insertion and conversion reaction products Li 0.98 MoO 2 and Li 2 O are close in space implies that MoO 2 and MoO 3 regions are well mixed at the microscale in MMO, while this is not the situation in the sample MMM. The much lower capacity in MMM is presumably associated with the large volume change of MoO 3 (104% volume change) during cycling2745 and the resulting aggregation and/or sluggish kinetics of lithium ion insertion for the MoO 2 nanoparticles2829. Since the MoO 2 and MoO 3 species are not well mixed at the microscale for MMM, inhomogeneous distribution causes phase isolation during cycling, which will lead to pulverization and rapid capacity decay.…”

Hierarchical Molybdenum Dioxide Microflowers Encapsulating Nickel Nanoparticles for High‐Performance Lithium‐Ion Battery Electrodes

“…All measured curves show a depressed semicircle in the high‐middle frequency range and an inclined straight line in the low frequency region. The simplified equivalent circuit composed of R e (contact/electrolyte resistance), R ct (charge‐transfer resistance), CPE dl (double‐layer capacitance between electrolyte and cathode), Warburg diffusion element W s (lithium ion diffusional component), and C i (lithium intercalation capacitance) is used to interpret the measured results ,,. Obviously, from the parameters of the equivalent circuit for Ni/MoO 2 /C and MoO 2 /C after fitting the diameter of the semicircular curve in Table S2.…”

Transition Metal Carbide Complex Architectures for Energy‐Related Applications

“…Similarly, MoO 2 /Mo 2 C/C spheres also have been synthesized through hydrothermal and calcination processes by using the resol precursor, triblock copolymer F127, and ammonium heptamolybdate tetrahydrate. MoO 2 /Mo 2 C/C spheres showed high lithium storage capacity, good rate capability, and good cycling performance due to their excellent electronic conductivity and ability of accommodating the volume variation …”

“…MoO 2 / Mo 2 C/C spheres showedh igh lithium storage capacity,g ood rate capability,a nd good cycling performance due to their excellent electronic conductivity and ability of accommodating the volume variation. [109] Compared with the hydrothermal/solvothermal methods, self-polymerization reactions can take place only after introducinga ni nducer.S elf-polymerization methods as energysaving tools have enriched the synthesis of TMC nanospheres. [63,102] For instance, pomegranate-like Mo 2 C@C nanospheres were typically synthesized by the self-polymerization approach, combined with as ubsequentc arbonation process.…”