Electrochemical Performance Enhancement of Nitrogen-Doped TiO₂ for Lithium-Ion Batteries Investigated by a Film Electrode Model

Abstract

Titanium dioxide (TiO2) is proposed as a promising anode material for lithium-ion batteries (LIBs) due to its highly stable structure and slight side reaction at the electrode/electrolyte interface. The low specific capacity and slow Li-ion diffusion kinetics are the major bottlenecks for the actual application of TiO2. It is thus important to exploit viable pathways to enhance the electrochemical performance and understand the corresponding mechanisms. In this work, high-quality amorphous TiO2 (TO) and anatase TiO2 (cTO) film electrodes are employed to investigate the bulk electrochemical performance by minimizing the surface contribution. At the same time, nitrogen (N) doping is performed for further comparison. The results show that TO has a relatively lower specific capacity than cTO. However, N-doped TO (TON) presents a specific capacity more than 4 times higher than TO and 3 times higher than cTO. TON also exhibits a significantly improved initial Coulombic efficiency (ICE) and a relatively higher Li-ion diffusion coefficient. Our study shows that the superior electrochemical performance of TON is correlated to the synergistic effects of the bulk pseudocapacitor and battery characteristics.

Defect‐rich bronze titanium dioxide ultrathin nanosheets supported on carbon nanotubes for enhanced lithium‐ion storages

“…When b ‐value is close to 0.5, the lithium‐ion storage mechanism belongs to the diffusion‐controlled type 9 while b ‐value of 1 suggests the capacitive contribution 55 . The linear fitting between anodic/cathodic peaks and scanning rates is shown in Figure 6B.…”

“…When b-value is close to 0.5, the lithium-ion storage mechanism belongs to the diffusion-controlled type 9 while b-value of 1 suggests the capacitive contribution. 55 F I G U R E 6 EIS curves before (A) and after cycling (B). CV curves (C) of the TiO 2 (B)-CNTs electrode at different scan rates and plots of CV peak current (D) of the cathodic reaction vs the scan rates in LIBs.…”

Nanowires-Assembled TiO2 Nanorods Anchored on Multilayer Graphene for High-Performance Anodes of Lithium-Ion Batteries

“…Another shortage of graphite anode is the lithium plating that easily occurs due to the low operation potential, which will cause a serious safety issue [ 5 , 6 ]. Recently, anode materials based on different lithiation mechanisms including insertion, alloying, and conversion were researched [ 7 , 8 , 9 , 10 , 11 ]. As a kind of insertion-type anode material, titanium dioxide (TiO 2 ) has many particular advantages due to its high theoretical specific capacity (336 mAh g −1 ), high reversible cyclic stability, and relatively high operational potential.…”

Europium modified TiO2 as a high-rate long-cycle life anode material for lithium-ion batteries

“…6 In these strategies, doping can effectively improve the conductivity of bulk TiO 2 . 7 In addition, when doping a cation into a Ti 4+ site of TiO 2 , the kinetics can be greatly improved and the electronic conductivity of the materials can be significantly increased, which helps to improve the capacity transport, cycle life and rate ability. 8 The reported dopants include Mo 5+ /Mo 6+ , 9 Fe 3+ , 10 Ti 3+ , 11 Mn 2+ , 12,13 Cu 2+ , 14 and Ni 2+ , 15 which increased the donor density of TiO 2 .…”