Freestanding interlayers for Li–S batteries: design and synthesis of hierarchically porous N-doped C nanofibers comprising vanadium nitride quantum dots and MOF-derived hollow N-doped C nanocages

Abstract

The introduction of functional interlayers between the cathode and anode in lithium–sulfur battery (LSB) technology results in significant improvements in electrochemical performance. Here, we developed hierarchically structured porous, conductive, and...

Nanofibers Comprising Interconnected Chain‐Like Hollow N‐Doped C Nanocages as 3D Free‐Standing Cathodes for Li–S Batteries with Super‐High Sulfur Content and Lean Electrolyte/Sulfur Ratio

“…Finally, the colloidal suspension was centrifuged, washed repeatedly, and dried in air to obtain uniform-sized ZIF-8 polyhedra. [3] To obtain a spinning solution, 3.0 g of the as-prepared ZIF-8 polyhedra was dispersed in 20 mL of DMF solution and stirred for 2 h followed by ultrasonication for another 1 h. Subsequently, 1.5 g of PAN was added slowly to the milky ZIF-8/DMF solution and stirred overnight for homogeneous mixing. The obtained spinning solution was loaded into a plastic syringe pump (12 mL capacity) fitted with a 21-gauge stainless-steel needle.…”

“…[18][19][20][23][24][25][26][27] The typical process of coating an active material slurry on an aluminum current collector has limitations because of the density difference between sulfur and its discharge product. [3] Owing to the large volume variation between sulfur and Li 2 S during the redox process, crack formation or pulverization of the electrodes is highly evident in conventional electrodes, which is even more pronounced in the case of high-sulfur content or highsulfur loading electrodes. [1] Additionally, the corrosion of metal current collector such as aluminum or stainless steel affects the functioning of LSBs employing highly concentrated polysulfides as active material.…”

“…The tremendous advances in Li-S batteries (LSBs) during the last decade have brought them to the forefront of several rechargeable battery technologies. [1][2][3][4][5][6][7][8][9][10] However, the commercialization of LSBs is still lagging compared to their counterparts owing to several fundamental drawbacks such as the highly insulating nature of sulfur and its discharge product, i.e., Li 2 S formation and migration of lithium polysulfide (LiPS) species, which results in the loss of active material, severe carbonization and employed it as the LSB cathode substrate. [28] Similarly, Guo et al synthesized and tested N-CNF electrodes for Li-LiPSs battery performance.…”

“…In particular, a Zn-based zeolitic imidazole framework (ZIF-8, a class of MOFs) was reported as a self-sacrificing template to develop porous interlayer materials owing to the volatile nature of the central Zn atom. [3] Other studies have also reported the synthesis of 1D porous carbon nanostructures using the conventional electrospinning method and MOFs. For example, MOF-derived porous CNFs, including interconnected bimodal pores have been applied to Li-Se battery applications.…”

Ultra‐Small Ferromagnetic Fe3O4 Nanoparticles Modified Separator for High‐Rate and Long Cycling Lithium‐Sulfur Batteries

“…[10] To overcome the above problems, the current effort is often dedicated to the search for new host materials, including carbon materials, [11][12][13] metal oxides, [14][15][16] metal sulfides, [17,18] and metal nitrides. [19][20][21][22] Few reports can be found on the research of separator and interlayer, [23] binder [24,25] and electrolyte. [26] Among them separator is a critical component that determines short-circuiting between the cathode and the anode.…”