Templated magnesiothermic synthesis of silicon nanotube bundles and their electrochemical performances in lithium ion batteries

Abstract

Silicon nanotube bundles (Si NBs) have been synthesized on a large scale via a templated magnesiothermic method.

Template‐Free Electrochemical Formation of Silicon Nanotubes from Silica

“…[12][13][14][15][16] Currently, Si-NT are mainly prepared by chemical vapor deposition (CVD) or template-assisted methods. [12,[17][18][19][20][21][22][23][24][25][26][27][28] However, the usage of toxic SiH 4 /SiCl 4 as raw materials and expensive gold as catalysts as well as the low production yield largely restrict the large-scale deployment of the CVD methods. [19][20][21]23] The template-assisted strategy requires tedious procedures including the construction of sacrificial templates, coating of Sicontaining precursors, extraction of Si, and removal of inner template.…”

“…[19][20][21]23] The template-assisted strategy requires tedious procedures including the construction of sacrificial templates, coating of Sicontaining precursors, extraction of Si, and removal of inner template. [12,[22][23][24][25][26][27][28] The preparation procedures become more complicated when an extra surface layer is coated via post-processing strategies to improve the performance of Si-NT. [11,29,30] Exploring practical methods for large-scale and low-cost preparation of Si-NT from affordable silicon sources as well as in situ coating strategy is an appealing but tough task.…”

“…Of note, molten salt electrolysis, which is widely adopted for production of metals in industry, has been verified to be adaptable for large-scale production of silicon nanomaterials. [31][32][33][34][35][36][37][38][39][40][41] Compared with the conventional CVD method which uses toxic SiH 4 /SiCl 4 as raw materials and suffers from low production yield, [12,[17][18][19][20][21][22][23][24][25][26][27][28] the molten salt electrolysis strategy with a high production yield herein uses affordable SiO 2 as the starting material and shows a promise for practical production of Si nanotubes.…”

Enhanced electrochemical performances of silicon nanotube bundles anode coated with graphene layers

“…Nanostructured silicon ranging from nanowires, nanofilms, nanotubes to nanoparticles and their composites, in which the strain can be relaxed easily without mechanical fracture because of their smaller size and available surrounding free spaces, have been exploited widely to alleviate the structure deterioration efficiently [6][7][8][9][10]. Si nanotube bundles (NBs) have been successfully synthesized at large scale in our previous work [11] via a magnesiothermic reduction method [12]. However, structural collapse still occurred during prolonged electrochemical reactions for these long Si tubes with length larger than several micrometers, hence resulting in unsatisfactory electrochemical performances.…”

A Bioinspired Nanofibrous Titania/Silicon Composite as an Anode Material for Lithium‐Ion Batteries

“…To address these drawbacks, one approachi st he fabrication of silicon-basedm aterials with variousn anoscale structures, such as nanospheres, [10,11] nanotubes, [12][13][14] nanowires, [15,16] and porouss tructures, [17,18] which have been explored previously.I t has been demonstrated that nanostructures of silicon-based materials shorten the pathway lengths of the lithium ions, increase the electrode-electrolyte contact area, and accommodate large volume changes,l eadingt oi mproved anode performances. In particular, as one of the advantages of porous materials tructures, [19] the porosity of silicon-basedm aterials provides as uperior configuration for accommodating volume changes and facilitatese lectron and ion transfer.H owever, the cycling performances of silicon-based anodesa re still limited by the introduction of only nanoscale structural features.…”