Interlayer Engineering of Molybdenum Trioxide toward High‐Capacity and Stable Sodium Ion Half/Full Batteries

Abstract

Orthorhombic molybdenum trioxide (MoO3) is one of the most promising anode materials for sodium‐ion batteries because of its rich chemistry associated with multiple valence states and intriguing layered structure. However, MoO3 still suffers from the low rate capability and poor cycle induced by pulverization during de/sodiation. An ingenious two‐step synthesis strategy to fine tune the layer structure of MoO3 targeting stable and fast sodium ionic diffusion channels is reported here. By integrating partially reduction and organic molecule intercalation methodologies, the interlayer spacing of MoO3 is remarkably enlarged to 10.40 Å and the layer structural integration are reinforced by dimercapto groups of bismuththiol molecules. Comprehensive characterizations and density functional theory calculations prove that the intercalated bismuththiol (DMcT) molecules substantially enhanced electronic conductivity and effectively shield the electrostatic interaction between Na+ and the MoO3 host by conjugated double bond, resulting in improved Na+ insertion/extraction kinetics. Benefiting from these features, the newly devised layered MoO3 electrode achieves excellent long‐term cycling stability and outstanding rate performance. These achievements are of vital significance for the preparation of sodium‐ion battery anode materials with high‐rate capability and long cycling life using intercalation chemistry.

VOPO4⋅2H2O Nanosheet Cathode for Enhanced Sodium Storage

“…However, the bulkier radius [1.02 (Na + ) vs. 0.76 Å (Li + )] makes the Na-ion diffusion more sluggish than that of Li-ions, resulting in the larger volume change, the lower special capacity and the poorer cyclical stability, which limit the further development of SIBs in large-scale energy storage system (Wang et al, 2018;Liu et al, 2020). Therefore, designing/exploring novel advanced electrodes for SIBs to facilitate fast Na-ion transfer is the top priority at present (Li C. et al, 2020;Wang B. et al, 2020).…”

Interlayer Chemistry of Layered Electrode Materials in Energy Storage Devices

“…As reported by Li et al., bismuththiol (DMcT) can be employed as an interlayer pillar in MoO 3 , through partial reduction and organic molecule intercalation. [ 61 ] First, layered MoO 3 was transformed into a negatively charged MoO 3 layer incorporating Na + using the chemical reduction process. Subsequently, DMcT was intercalated into the interlayer using the ion‐exchange process to form a DMcT‐pillared MoO 3 structure (DMcT‐MoO 3 ).…”

Regulation of Cathode‐Electrolyte Interphase via Electrolyte Additives in Lithium Ion Batteries

“…It has the typical advantages of low cost and no toxicity while the drawback is the iron dissolution. [104] The commercial success of LiFePO 4 has also promoted the development of polyanionic cathode materials in sodium ion batteries (SIBs) [105,106] . LFP will form amorphous LiFePO 4 (OH) due to the presented Fe (III) on the surface through corrosion-type reaction, and the rich -OH groups on the surface will further react with LiPF6-based electrolyte, resulting in continuous side reactions such as iron dissolution and electrolyte decomposition.…”