Hydrogenated Anatase and Rutile TiO₂ for Sodium-Ion Battery Anodes

Abstract

Defective transition metal oxides prepared via a hydrogenation treatment have attracted growing attention for use as electrode materials of batteries and supercapacitors due to their improved electrochemical properties. In this work, two TiO 2 phases, namely, rutile (TiO 2 -R) and anatase (TiO 2 -A), and their hydrogenated phases (denoted with the prefix "H") are investigated as anodes for sodium-ion batteries. The charge− discharge properties of both phases can be enhanced via a highpressure hydrogenation treatment. For example, H-TiO 2 -A exhibits exceptional high-rate performance (100 mA h g −1 at 10,000 mA g −1 vs 5 mA h g −1 at the same current rate for TiO 2 -A) and great cycling stability (80% capacity retention after 4500 cycles). The introduction of oxygen vacancies increases the electronic and ionic conductivity of TiO 2 and the disordered structure offers more active sites for electrochemical reactions. The H-TiO 2 -R and H-TiO 2 -A electrodes are compared for sodium-ion battery applications. The superior performance of the former electrode is supported by the generalized gradient approximation Perdew−Burke− Ernzerhof density functional calculation.

Effects of Elemental Modulation on Phase Purity and Electrochemical Properties of Co‐free High‐Entropy Spinel Oxide Anodes for Lithium‐Ion Batteries

“…This is ascribed to the high O v concentration of 4 M Cu (Figure 3h), which can modulate the electronic structure and promotes Li + transport. [ 60,61 ] The R ct and D Li + values are in line with the high‐rate performance of the oxide electrodes.…”

In situ synthesis of nanostructured Fe3O4@TiO2 composite grown on activated carbon cloth as a binder-free electrode for high performance supercapacitors

“… 36,37 Two satellite signals of Fe2p 3/2 and Fe2p 1/2 peaks were observed at the same time, which can be attributed to the oxidation states of Fe 3+ and Fe 2+ in Fe 3 O 4 nanoparticles. 38,39 Two strong peaks of rutile type crystals are shown in the Ti2p spectra ( Fig. 4(b) ), and the binding energies are 458.8 eV (Ti 3+ ) and 464.5 eV (Ti 4+ ) respectively, which correspond to the two chemical energy levels of Ti2p 3/2 and Ti2p 1/2 .…”

Na4Co3(PO4)2P2O7/NC Composite as a Negative Electrode for Sodium-Ion Batteries

“…The observed sharp cathodic peak at around 0.2 V is mostly due to the decomposition of the electrolyte and the film formation at the solid electrolyte interphase (SEI) in the first scan only as the peak disappears in subsequent cycles. 39,40 The SEI is of crucial importance to the battery performance as it protects the anode by inhibiting the transfer of electrons from the anode to the electrolyte, while allowing only sodiumion diffusion. Moreover, the reversible peaks appear at 0.01 V in the cathode region and 0.09 V in the anodic region due to the intercalation and deintercalation of Na ions in the carbon matrix.…”