Porous Silicon–Carbon Composite Materials Engineered by Simultaneous Alkaline Etching for High-Capacity Lithium Storage Anodes

SiO2/Carbon Composite Microspheres with Hollow Core–Shell Structure as a High‐Stability Electrode for Lithium‐Ion Batteries

“…The stable SEI film formed on the surface of the SiO 2 /po‐C@C makes the charge transfer resistance reduced performing in the smaller semicircle of the SiO 2 /po‐C@C . At the middle‐frequency region, the semicircle diameter is much smaller in SiO 2 /po‐C@C than in the SiO 2 @C, which reflects that the charge transfer resistance (R CT ) between electrolyte and active materials in the former is far less than that in the latter contributing to a high electronic conductivity in SiO 2 /po‐C@C. The reason for the phenomenon is that the porous carbon skeleton provides the convenient electron transfer paths in SiO 2 /po‐C@C . In the low‐frequency region, obviously, as‐prepared materials possess the approximately vertical straight line associated with the Warburg diffusion impedance (W) revealing excellent lithium ions diffusion efficiency.…”

Top‐Down Synthesis of Silicon/Carbon Composite Anode Materials for Lithium‐Ion Batteries: Mechanical Milling and Etching

“…The particle size of Si can be directly reduced by ball‐milling. Sohn et al . showed a simple, scalable, low‐cost, and nontoxic process to produce porous Si/C anodes using facile ball‐milling followed by carbonization of pitch and alkaline etching of Si, as described in Figure .…”

“…(f) Voltage profiles; (g) cycling performance; and (h) CEs of non‐porous, less porous, and porous Si/C composites. (i) Rate capability of porous Si/C composite . Reused with permission.…”

Research Progress of Silicon/Carbon Anode Materials for Lithium‐Ion Batteries: Structure Design and Synthesis Method

“…For tackling the problem of complex, expensive and environmentally harmful of ordinary preparation for porous Si/C composites, Sohn et al [48] proposed a porous silicon-carbon (SiÀ C) composite using a scalable and nontoxic method in which Si and carbon were etched by alkaline solution. As a result, the composite exhibits high rate performance of about 1180 and 990 mAh g À 1 at rate of 0.1 and 5 A g À 1 , respectively due to abundant pores both in Si and carbon phase.…”

“…Researchers found that the problems of acid consumption and Si yield can be effectively solved by simply changing the sequence of the ball-milling and acid etching. [45,48,69] There are many parameters that affect the quality of the products. Among them, the ball-milling time has great influence on the particle size of the obtained products.…”