Improved electrochemical performance of nitrogen doped TiO₂-B nanowires as anode materials for Li-ion batteries

Abstract

N-doped TiO 2 -B nanowires are prepared by the solvothermal method using TiN nanoparticles as the starting material. X-ray photoelectron spectroscopy shows that the N dopants preferentially occupy the interstitial sites of TiO 2 -B up to a content of ∼0.55 at%. Above this critical value, the N dopants will substitute the oxygen atoms which improve the electronic conductivity of TiO 2 -B. The maximum proportion of substituted-N in the TiO 2 -B nanowires is ∼1.3 at%. Raman scattering shows that the substituted-N strengthens the Ti(1)-O 1 -Ti(2) and O 1 -Ti(1)-O 3 bonds of TiO 2 -B. This improves the stability of the corresponding local structures, thus reducing the distortion of the Li + diffusion channel along the b-axis of TiO 2 -B. As a result, the substituted-N has more of an impact on the electrochemical properties of TiO 2 -B than the interstitial-N does. The TiO 2 -B nanowires containing substituted-N dopants exhibit a remarkably enhanced electrochemical performance compared to pure TiO 2 -B. They show a discharge capacity of 153 mA h g −1 at the 20 C rate with a capacity retention of 76% after 1000 cycles. In addition, they can deliver a discharge capacity of 100 mA h g −1 at an ultra-high rate of 100 C, indicating their great potential in high power lithium ion batteries.

Si‐, Ge‐, Sn‐Based Anode Materials for Lithium‐Ion Batteries: From Structure Design to Electrochemical Performance

“…Although the Si nanoparticles showed limited capacity retention during the initial 100 cycles, the material delivered a high specific capacity of 1180 mA h g −1 after 500 cycles with only 0.1% decay per cycle (Figure C), suggesting improved cyclability at high current densities. To further improve the structure stability and electrochemical performance, other 0D nanostructured materials based on M anodes have also be intensively studied, including hybrid nanoparticles, hollow nanoparticles, and core–shell‐structured particles . Xu and co‐workers have synthesized nano‐Sn/C composite nanoparticles with nanosized Sn homogeneously dispersed in a spherical carbon matrix through a one‐aerosol‐spray pyrolysis method ( Figure A,B).…”

Computational insights into structural, electronic and optical characteristics of GeC/C2N van der Waals heterostructures: effects of strain engineering and electric field

“…30 Both GeC and C 2 N monolayers exhibit the semiconducting behavior with the direct band gap of about 2 eV. 21,23 The electronic, transport and optical properties of GeC and C 2 N monolayer can be tuned by strains engineering, 31,32 electric eld, 33,34 surface adsorption and functionalization. [35][36][37] These properties make GeC and C 2 N materials to be suitable for the design of high-performance nanodevices.…”

Ultrafast Nanocrystalline‐TiO2(B)/Carbon Nanotube Hyperdispersion Prepared via Combined Ultracentrifugation and Hydrothermal Treatments for Hybrid Supercapacitors

“…Nano‐TiO 2 (B)/carbon composites using activated carbon fiber or reduced graphene oxide have less TiO 2 (B) reagglomeration, but often produce the undesirable growth of TiO 2 (B) in b ‐axis dimension . Introducing nitrogen atoms either on TiO 2 (B) (N‐doped TiO 2 (B)) or the composite carbon (N‐doped graphene) further improved the rate‐capability of TiO 2 (B), yet failed to maintain the 50% capacity retention over 100 C.…”

“…The dispersion of TiO 2 (B) nanoparticles within the carbon matrix is one of the key features for achieving high rate capability. Distinct from previous studies, the ultracentrifugation process (UC treatment) with follow‐up hydrothermal treatment allows the formation of single‐nanosized and hyper‐dispersed TiO 2 (B) on the surface of MWCNTs. First, the successful TiO 2 (B) formation was confirmed by the XRD pattern (Figure S1, Supporting Information), where only small peaks of TiO 2 rutile due to the agglomeration of rutile particles can be seen (Figure S2, Supporting Information).…”