Amorphous TiO 2 inverse opal anode for high-rate sodium ion batteries

Abstract

Potential applications of sodium-ion batteries (SIBs) have motivated significant research interest in grid-scale energy storage. However, large radius of Na ions results in different electrochemical behaves. Therefore, synergistic understanding of the differences is greatly interested for future development of SIBs. Surface availability for ions with poor affinity to electrode materials is critical to rate performance in SIBs, but yet has rarely been reported. Here, to overcome the obstacles of material platform, amorphous TiO2 inverse opal is employed as a proof-of-concept prototype to illuminate the effects of surface ion availability and its relationship between solvent wettability and rate capability. Within expectation, superior rate capabilities are 2 achieved in return for enhanced solvent wettability, regardless of the type of electrolyte and the ion concentration in electrolyte. Even when the anode is cycled at a current density as high as 5000 mA g-1 , the reversible capacity could still retain a high value of ~113 mA h g-1. Our concept opens up a promising avenue to realize full potential of designing electrode materials for SIBs by adjusting the surface kinetics. This understanding shall extend the design principle to electrode materials for highly effective energy storage using other transport ions and other storage mechanisms.

TiO2 Nanostructures as Anode Materials for Li/Na‐Ion Batteries

“…This improvement was ascribed to the smaller primary particle size (7 nm) and good accessibility of the electrolyte inside the A7‐25 mesocrystal. Importantly, one possible drawback of nanostructured electrodes is electrolyte wettability ,. The good textural properties of the anatase TiO 2 mesocrystals assure efficient wettability for all nanostructure volume, improving the electrochemical properties of the electrode.…”

“…As in LIBs, Na‐ion uptake for various TiO 2 polymorphs (anatase, rutile, hollandite and the TiO 2 bronze (TiO 2 ‐B)) has been reported . In addition to these polymorphs, other authors have studied amorphous TiO 2 and even TiO 2 with dual phases ,. Ultimately, as mentioned earlier the electrochemical response of TiO 2 anodes for NIBs not only depends on crystal structure, but also depends on microstructural and textural features, processing and stability of solid electrolyte interfaces.…”

Heterostructured TiO2 Spheres with Tunable Interiors and Shells toward Improved Packing Density and Pseudocapacitive Sodium Storage

“…[20,24] In addition, the TiO 2 -S electrode displays typical battery-like galvanostatic profiles, indicating the limited surface-controlled charge storage. [28,[35][36][37][38][39][40] On the other side, cycling properties of the different TiO 2 anodes at constant currents are also tested in detail. As can be seen, the specific capacities of TiO 2 -HS are similar with that of TiO 2 -YB, but much larger than that of TiO 2 -S at lower current densities.…”

“…After the first several cycles, the curves illustrate apparent high voltage plateaus and become well overlapped, suggesting much safer sodium storage by avoiding the dendritic growth, as well as favorable capacity reversibility. [24][25][26][27][28][29][35][36][37][38][39][40] The irreversible loss of capacity in these anodes can in some cases be offset by prelithiation/sodiation technologies. [41,42] Figure 3d demonstrates the cycling properties of the three as-prepared TiO 2 samples at low rate of 0.2 A g −1 .…”

In Situ Growth of a Feather‐like MnO2 Nanostructure on Carbon Paper for High‐Performance Rechargeable Sodium‐Ion Batteries

“…Recently, tuning crystallographic structure of oxides to improve the diffusion and transport of electrolyte ions have become a hot research topic . Transition metal oxides have been traditionally used as anode materials for LIBs and SIBs, such as TiO 2 , Fe 3 O 4 ,, CuO,, NiCo 2 O 4 ,. Among various transition metal oxides, manganese oxide have attracted a great many attention for their different oxidation states of manganese, the low toxicity, the low cost, and superior safety .…”