N-rich porous Si@SiOx/NC composites derived from in situ polymerisation of acrylic acid as anode for Li-ion batteries

Three-Dimensional Porous Si@SiOx/Ag/CN Anode Derived from Deposition Silicon Waste toward High-Performance Li-Ion Batteries

“…There are no spectral peaks corresponding to Na and Cl elements, implying that the Nacl template has been completely removed during the washing process. In the Si 2p spectrum (Figure b), the small peak at 99.5 eV is corresponding to Si 0 , and the peaks from 101 to 105 eV are attributed to Si 2+ , Si 3+ , and Si 4+ , respectively. , According to Figure c, the two split peaks at 368.2 and 374.2 eV of Ag 3d (the distance of the two peaks is about 6 eV) attributed to Ag 0 , whereas the weak peaks at 366.9 and 372.8 eV belong to Ag + . ,, In the N 1s spectrum (Figure d), two primary peaks at 398.4 and 400.8 eV and a weak peak at 403.2 eV are attributed to pyridinic-N, pyrrolic-N, and graphitic-N, respectively. , The two strong peaks of pyridine N and pyrrole N are associated with the electron-donating ability of the composites, which can support more Li + active sites in the materials, while graphite N enhances the conductivity of the composites. , Figure e shows the spectrum of C 1s, and the binding energies of 284.5, 285.2, 286.2, and 288.7 eV are correlated with C–C, C–O/C–N, carbonyl and O–CO species, respectively. , This further illustrates the presence of heteroatoms N and heteroatoms C of the prepared composites after chitosan carbonization . The schematic diagram of different types of N atom doping C atoms is illustrated in Figure f …”

“…26,34 The two strong peaks of pyridine N and pyrrole N are associated with the electron-donating ability of the composites, which can support more Li + active sites in the materials, while graphite N enhances the conductivity of the composites. 26,27 Figure 5e shows the spectrum of C 1s, and the binding energies of 284.5, 285.2, 286.2, and 288.7 eV are correlated with C−C, C−O/ C−N, carbonyl and O−C�O species, respectively. 26,34 This further illustrates the presence of heteroatoms N and heteroatoms C of the prepared composites after chitosan carbonization.…”

“…In the last few years, many scientific researchers were committed to solving the inherent bottleneck of silicon anodes to successfully apply silicon waste to high-performance lithium-ion batteries. The relevant studies have shown that grinding silicon waste to the nanoscale can availably enhance the cycle stability of electrodes. − Besides, silicon/carbon composite materials accompany excellent conductivity, outstanding buffering effect, and low cost, which have been deemed as the most hopeful silicon-based anode materials. ,− At the same time, a large number of experimental and theoretical studies have demonstrated that nitrogen-doped carbonaceous materials can effectively increase the defective site. − These sites on the surface of composites provide active electrochemical sites that boost the Li + mobility path, which further improves the reversible capacity and rate performance. ,,, Furthermore, the microstructure design of the silicon waste anode also has a significant influence on electrochemical performance; especially, the porous structure can obviously enhance the cycle performance of electrodes. ,,, More specifically, the structure design of porous silicon can alleviate the volume expansion of the silicon anode during lithiation/delithiation; ,, besides, the construction of a porous carbon network structure can accommodate the swell of silicon nanoparticles while providing fast channels for ion and electrode transport. , Despite this, the practical application of the silicon waste anode was severely hampered by the rapid degradation of cycle performance.…”

Toward the Improvement of Silicon-Based Composite Electrodes via an In-Situ Si@C-Graphene Composite Synthesis for Li-Ion Battery Applications

“…These methodologies include CVD, sol-gel synthesis, in situ synthesis, (laser) pyrolysis, carbonization, thermal plasma, or the elaboration of complex structures as the “Yolk-Shell” type [ 13 , 14 , 15 , 16 , 17 , 18 ]. Current trends also show that these C shells can be N-doped to enhance conductivity and wettability, and this buffer layer concept is also applied to other intercalation compounds displaying high volume change upon cycling [ 19 , 20 ].…”