Yolk–Shelled C@Fe₃O₄ Nanoboxes as Efficient Sulfur Hosts for High‐Performance Lithium–Sulfur Batteries

Abstract

Owing to the high theoretical specific capacity (1675 mA h g ) and low cost, lithium-sulfur (Li-S) batteries offer advantages for next-generation energy storage. However, the polysulfide dissolution and low electronic conductivity of sulfur cathodes limit the practical application of Li-S batteries. To address such issues, well-designed yolk-shelled carbon@Fe O (YSC@Fe O ) nanoboxes as highly efficient sulfur hosts for Li-S batteries are reported here. With both physical entrapment by carbon shells and strong chemical interaction with Fe O cores, this unique architecture immobilizes the active material and inhibits diffusion of the polysulfide intermediates. Moreover, due to their high conductivity, the carbon shells and the polar Fe O cores facilitate fast electron/ion transport and promote continuous reactivation of the active material during the charge/discharge process, resulting in improved electrochemical utilization and reversibility. With these merits, the S/YSC@Fe O cathodes support high sulfur content (80 wt%) and loading (5.5 mg cm ) and deliver high specific capacity, excellent rate capacity, and long cycling stability. This work provides a new perspective to design a carbon/metal-oxide-based yolk-shelled framework as a high sulfur-loading host for advanced Li-S batteries with superior electrochemical properties.

A Comprehensive Review of Materials with Catalytic Effects in Li–S Batteries: Enhanced Redox Kinetics

“…This beneficial phenomenon is not applicable to most other catalytic metal oxides, including Fe 2 O 3 , Fe 3 O 4 , La 2 O 3 , Nb 2 O 5 , and RuO 2 , with redox potentials lower than 2.0 V. Instead, their mechanisms of catalytic activity involve chemical interactions with LiPS. Thus, a mechanistic understanding of how chemical interactions influence the redox kinetics is important.…”

Metal‐Organic Framework‐Derived Carbons for Battery Applications

“…[105] Due to its high theoretical capacity of 1675 mAh g −1 with a specific energy of 2500 Wh kg −1 , abundance in the Earth's crust, and environmental friendliness, S is becoming the most promising candidate for cathode materials for next-generation Li batteries. Consequently, there are some techniques available to tackle those problems, e.g., embedding S into PC materials by physical absorption, [107][108][109][110][111][112] strengthening sulfur species with MO additives through chemical adsorption, [113][114][115] and coating S with conductive polymers by physical blocking. Furthermore, the introduction of conductive additives results in the inadequate applications of active materials.…”

Recent Progress in Iron‐Based Electrode Materials for Grid‐Scale Sodium‐Ion Batteries

“…Other anode materials, such as FeOOH and MFe 2 O 4 (M = Cu, Co, Mg), were also reported; they exhibited similar conversion reaction mechanisms, but their cycling stability needed to be improved. In addition, the FeO x and FeS x materials have been introduced to the carbon matrix as internal polysulfide reservoirs in lithium sulfur batteries, which reduces the shuttle effect and thus leads to improved electrochemical performance …”