Metal-organic framework-based catalysts for lithium-sulfur batteries

Three-dimensional graphene/metal–organic framework composites for electrochemical energy storage and conversion

“…Due to the abundant resources and high theoretical energy density of the active material sulfur, LSBs with high theoretical specific capacity have attracted much attention. 4,34 However, there are still some problems in LSBs, e.g., the dissolution of polysulfide lithium products in electrolyte, the dendrite growth of lithium metal in the cathode, poor conductivity of sulfur and large volume change during the battery charge/discharge process. 107,108 The design and synthesis of electrode materials with good conductivity, porous flexibility and robustness can effectively improve the above problems.…”

“…As emerging ordered crystal materials, metal-organic frameworks (MOFs) are composed of metal ions or clusters and organic ligands through covalent bonds, coordination bonds and intermolecular forces. [1][2][3][4] The variable metal centers and organic ligands of MOFs give them structural and functional diversity. [5][6][7][8][9] Because of their large surface area, high porosity and unique photoelectric effect, MOFs and their derivatives (i.e., porous carbon and metal compounds) have been widely used in the field of electrochemistry.…”

Donor–Acceptor Conjugated Microporous Polymer toward Enhanced Redox Kinetics in Lithium–Sulfur Batteries

“…Lithium–sulfur (Li–S) batteries are recognized as one of the most promising alternatives for new generation energy storage devices due to their ultrahigh intrinsic capacity (1675 mAh g –1 ) and theoretical specific energy density (2600 Wh kg –1 ) as well as the low price and environmental friendliness of sulfur. − However, the practical use and commercialization of Li–S batteries still face many challenges, such as low sulfur utilization, irreversible capacity fading and low Coulombic efficiency, which are mainly caused by the insulation of solid elemental sulfur and lithium sulfide (Li 2 S), the huge volume fluctuation of the sulfur cathode and the shuttle effect of soluble polysulfide intermediates (LiPSs). − Besides, the electrochemical redox kinetics is always sluggish, especially in the case of lean electrolyte and high sulfur loading, thereby leading to incomplete conversion of active species and apparent LiPS flooding. − …”

Covalently introducing sulfur in a thiol-rich metal-organic framework toward advanced lithium-sulfur batteries

“…Lithium-sulfur batteries as one of the most promising next-generation battery technologies, have received increasing attention owing to their high gravimetric energy density and discharge capacity. [1][2][3][4][5] However, the practical application of Li-S batteries is impeded by various issues including the poor conductivity of sulfur and lithium sulfide, massive volume expansion of sulfur upon lithiation, severe shuttle effect of polysulfide intermediates, and the sluggish reaction kinetics. [6][7][8][9][10][11] Specifically, the shuttle effect resulted from polysulfide dissolution/diffusion, and the sluggish conversion process between different polysulfide species during charging and discharging results in low sulfur utilization and poor cycling stability.…”