Structure and physical properties of Li4Ti5O12 synthesized at deoxidization atmosphere

Abstract

Powders of spinel Li 4 Ti 5 O 12 (LTO) were successfully synthesized at reducing conditions by solid-state method. The structure and physical properties of Li 4 Ti 5 O 12 were examined by X-ray diffraction (XRD), Raman spectroscopy, scanning electronic microscopy (SEM), and differential capacitance, respectively. XRD shows that both samples are single-phase spinel compounds. LTO synthesized in Ar/H 2 (8% mol) has a larger lattice parameter than that in Ar. SEM indicates that all of the prepared powders have the uniform, nearly cubic structure morphology with narrow size distribution in the range of 200-300 nm. Raman spectra indicate that the Raman bands corresponding to the Ti-O vibration has a blue shift from 674 to 680 cm −1 due to the few H 2 in the synthesized condition, indicating that there is very few oxygen vacancies in the Li 4 Ti 5 O 12 synthesized under Ar/H 2 (8% mol). The dQ/dV vs. voltage plots reveals the redox potentials for the synthesized Li 4 Ti 5 O 12 -negative electrode materials.

One‐Step Synthesis of Highly Oxygen‐Deficient Lithium Titanate Oxide with Conformal Amorphous Carbon Coating as Anode Material for Lithium Ion Batteries

“…Chiang and co‐workers summarized available electronic conductivity data for LTO, in which the defective‐LTO (with oxygen vacancies) was of the highest reported electronic conductivity . Therefore, it has gotten great interest and numerous researchers had engineered processes to generate oxygen vacancies in the LTO structure . With amorphous carbon coating, Chen and co‐workers demonstrated lower Li ion (Li + ) interfacial transfer resistance which dramatically enhanced the battery performance .…”

High-Energy-Density LiNi0.8Co0.15Al0.05O2 and Dual-Phase LTO-R-TiO2 Materials via a Microwave-Assisted Reaction: Alleviating the Capacity Fading Mechanism by Nanocoating of Al2O3 and PEDOT

“…To understand the reaction kinetics of the negative electrodes, the CV profile demonstrates a characteristic signature of spinel-type LTO, which demonstrates two main reduction peaks located at around 1.77 and 1.37 V vs Li/Li + . The LTO- R -TiO 2 /PEDOT electrode prepared by MW-HT and MW-SS methods reveals a pair of sharp redox peaks at about 1.51 and 1.64 V, which demonstrates distinctive insertion/extraction with a controlled diffusion process. , …”

“…The LTO-R-TiO 2 /PEDOT electrode prepared by MW-HT and MW-SS methods reveals a pair of sharp redox peaks at about 1.51 and 1.64 V, which demonstrates distinctive insertion/extraction with a controlled diffusion process. 59,60 In contrast, the redox pairs of the pristine LTO-R-TiO 2 electrode were centered at 1.45 and 1.70 V with ΔE v of 0.25 V compared to the polymer-based electrode with ΔE v of 0.13 V. This implies that the Li + lithiation/delithiation process in the (342 and 410 nm). The band-gap energies (E g ) were calculated using eq 1.3, and the corresponding Tauc plot is shown in Figure 8f.…”

A template-free synthesis and structural characterization of hierarchically nano-structured lithium-titanium-oxide films

“…Bulk Li 4 Ti 5 O 12 shows, however, Raman bands at 165 cm À1 (bending vibration of the O-Ti-O bond), 233 cm À1 (bending vibration of the O-Li-O bond), 344 and 424 cm À1 (stretching vibration modes of Li-O bonds in LiO 4 and LiO 6 ) and 674 cm À1 (vibration modes of Ti-O bonds in TiO 6 octahedra). 36,37 The Li 2 TiO 3 bulk material shows on the other hand bands at 355 cm À1 (Li-O stretching vibrations in LiO 6 octahedra), 422 cm À1 (Li-O stretching vibrations in LiO 4 octahedra) and 663 cm À1 (Ti-O stretching vibrations in TiO 6 octahedra). 38,39 The absence of the Raman bands of both compounds may be explained based on the Raman measurement being local, compared to XRD.…”