Mass‐Production of Electrospun Carbon Nanofiber Containing SiO_x for Lithium‐Ion Batteries with Enhanced Capacity

Abstract

of carbon-based material is 372 mAh g −1 , and it is almost achieved in various research fields. [12][13][14][15][16][17][18] As alternative candidate for the LIB anode, recent studies focused on siliconbased materials and especially on single crystalline silicon that exhibits a theoretical capacity of ≈3579 mAh g −1 of (ten times that of carbon-based materials). [19][20][21] Unfortunately, silicon-based materials exhibit a crucial limitation in terms of their use as the active material of an anode. The silicon-based active materials expand their volume up to 300% from the initial volume during the charge/discharge process. [22][23][24] The expansion of silicon leads to the destruction of initial architecture of the active material and results in a significant decrease in the capacity. Several methods are reported to overcome the drawback and include nano-structuring of silicon, [25][26][27][28][29][30][31] and yolk shell structure, [22,[32][33][34] although they are still insufficient in terms of providing good stability in the charge/discharge process. Specifically, Silicon oxide (SiO x )based materials that exhibit more oxygen than single crystal silicon provide several benefits to overcome the limitations of both carbon-and silicon-based materials. Although SiO x -based materials exhibit relatively lower capacity than that of single silicon, their volumetric expansion is significantly lower since the oxygen prevents the phase transition of silicon crystalline and provides high stable cycle retention. Additionally, the SiO x structure includes Si elements in its chemical structure, and thus the material exhibits a higher capacity than carbon-based materials. [35][36][37][38] Additionally, it is also important to perform the micro-structuring of active materials since the structure directly affects electrical properties. Among the micro-structuring of active materials, the electrospun nanofiber that exhibits straight continuous fibril structures exhibits significantly low resistance and high capacity of the LIB since the structure provides an electron-conductive pathway and a narrow lithium-ion diffusion layer. [39][40][41] However, despite the aforementioned advantages, the practical usage of electrospun nanofiber in the industry is poor, and this is mainly due to the low productivity of electrospinning. [42,43] Our team previously reported on a syringeless electrospinning system by using a helically probed rotating cylindrical structure (HPRC). [44,45] The system Carbon Nanofibers In this study, electrospun carbon nanofibers hybridized with silicon oxide (SiO x ) are prepared by using a syringeless electrospinning system of polyacrylonitrile (PAN) solution containing tetraethylorthosilicate (TEOS) via a sequential pyrolysis process. The syringeless electrospinning system provides a large number of composite nanofibers in a short time, and the obtained composite nanofibers exhibit uniform diameter and morphology. The composite nanofiber is converted into a carbon nanofiber containing SiO x via a simple pyrolys...

3D jet writing of mechanically actuated tandem scaffolds

“…Last, the CREW process provides benefits in terms of high-throughput production compared to the previous system. It is generally difficult to expand electrospinning methods into multinozzle systems because increasing the number of needles will induce electrical interference between individual nozzles (15,(58)(59)(60). However, here, because the voltage is applied to the collector, it is possible to increase the number of needles, while avoiding substantial interferences between the parallel polymer jets.…”

A Review of Recent Advancements in Electrospun Anode Materials to Improve Rechargeable Lithium Battery Performance

“…Most of these efforts have been focused on silicon oxides (SiO x ) and silicon/carbon composites. The silicon oxides (SiO x ) are expected to maintain long-term stable cycling performances as they can effectively accommodate the volume change of Si to SiO 2 matrix into the SiO x structure [ 222 ]. The major disadvantages associated with the materials are a low electrical conductivity, low lithium mobility, and a huge irreversible capacity loss owing to the formation Li 2 O and Li 4 SiO 4 from the SiO 2 phase [ 223 ].…”

Colloid Syringeless Electrospinning toward Nonwoven Nanofiber Web Containing a Massive Amount of Inorganic Fillers

“…[13][14][15][16][17][18][19][20] We have also recently reported "syringeless electrospinning," which is a modified needleless electrospinning. [21][22][23] In this method, a relatively lower voltage was required compared to usual needleless electrospinning, due to easier mechanism forming Taylor cone. [21][22][23] Therefore, this method can not only contribute to the mass production of the material, but also is a powerful technique to expand type of polymers due to their easy formation of Taylor cone with relatively low voltage.…”

“…[21][22][23] In this method, a relatively lower voltage was required compared to usual needleless electrospinning, due to easier mechanism forming Taylor cone. [21][22][23] Therefore, this method can not only contribute to the mass production of the material, but also is a powerful technique to expand type of polymers due to their easy formation of Taylor cone with relatively low voltage. One of the significant merits of syringeless electrospinning will be the possibility to make it versatile for "colloidal electrospinning."…”