The role of the oxide shell on the stability and energy storage properties of MWCNT@TiO nanohybrid materials used in Li-ion batteries
Por:
Muniz, Jesus, Rincon, Marina E., Acevedo-Pena, Prospero
Publicada:
6 jul 2016
Categoría:
Physical and Theoretical Chemistry
Resumen:
Core@shell nanohybrids as MWCNT@TiO are a reliable alternative in the
use of electrode materials for Li-ion batteries, since the specific
capacity is enhanced as compared to pristine MWCNT and TiO. Shell
thickness and the degree of disorder appear to play an important role in
such behavior at the graphene interface/oxide. We performed molecular
dynamics and DFT calculations to understand the nature of bonding at the
nanohybrid interface and the degree of disorder caused by the bonding of
the oxide on the graphene surface. Growing of shell thickness with
increasing number of TiO nanoparticles was simulated using a reactive
force field, and an optimum configuration was found. Shell size plays a
dominant role in the rising of enhanced electronic states around the
Fermi level, increasing chemical capacity. Interestingly, at the optimum
shell thickness, stability of the MWCNT is not compromised and the value
of the density of states at the Fermi level is the largest. This
provides the structural features to improve the design of core@shell
materials for Li-ion batteries. It may be of particular relevance to
synthesize composites based on MWCNT to improve performance of several
materials for Li-ion storage, since the same trend can be expected to
other systems.
Filiaciones:
Muniz, Jesus:
Univ Nacl Autonoma Mexico, Inst Energias Renovables, Col Ctr, Priv Xochicalco S-N, Temixco 62580, Morelos, Mexico
Univ Nacl Autonoma Mexico, CONACYT, Col Ctr, Priv Xochicalco S-N, Temixco 62580, Morelos, Mexico
Rincon, Marina E.:
Univ Nacl Autonoma Mexico, Inst Energias Renovables, Col Ctr, Priv Xochicalco S-N, Temixco 62580, Morelos, Mexico
Acevedo-Pena, Prospero:
Univ Nacl Autonoma Mexico, Inst Energias Renovables, Col Ctr, Priv Xochicalco S-N, Temixco 62580, Morelos, Mexico
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