Space‐Confined Atomic Clusters Catalyze Superassembly of Silicon Nanodots within Carbon Frameworks for Use in Lithium‐Ion Batteries

Abstract

Incorporating nanoscale Si into a carbon matrix with high dispersity is desirable for the preparation of lithium‐ion batteries (LIBs) but remains challenging. A space‐confined catalytic strategy is proposed for direct superassembly of Si nanodots within a carbon (Si NDs⊂C) framework by copyrolysis of triphenyltin hydride (TPT) and diphenylsilane (DPS), where Sn atomic clusters created from TPT pyrolysis serve as the catalyst for DPS pyrolysis and Si catalytic growth. The use of Sn atomic cluster catalysts alters the reaction pathway to avoid SiC generation and enable formation of Si NDs with reduced dimensions. A typical Si NDs⊂C framework demonstrates a remarkable comprehensive performance comparable to other Si‐based high‐performance half LIBs, and higher energy densities compared to commercial full LIBs, as a consequence of the high dispersity of Si NDs with low lithiation stress. Supported by mechanic simulations, this study paves the way for construction of Si/C composites suitable for applications in future energy technologies.

N-doped porous carbon nanofibers sheathed pumpkin-like Si/C composites as free-standing anodes for lithium-ion batteries

“…However, the electrochemical performance has not been significantly improved due to the unstable SEI formation and intrinsically low conductivity. To mitigate these problems, the strategy is to introduce conductive carbonaceous material to the Si anode, which can notably promote favorable SEI formation and enhance the conductivity of Si [24,25]. As a result, the electrochemical performance of the Si anode is improved.…”

Biomass‐Derived Hierarchically Porous (Nitrogen, Phosphorus) Co‐Doped SiOx/C Composite Nanosheet Architectures for Superior Lithium Storage and Ultra‐Long Cycle Performance

“…Lithium-ion batteries (LIBs) have been successfully commercialized to meet the demands of continually growing energy and global CO 2 emission reduction as indispensable energy storage devices because of long cycle stability, and high energy density and working potential. [1][2][3] As a result, both novel cathode [4] and anode materials such as carbon-, [5,6] silicon-, [7][8][9] and tin-based anode materials, [10] with high capacity, long-term stability and environmental friendliness are highly desired for next-generation power systems. [3,[11][12][13] Currently, conventional intercalation-type graphite anode materials are largely restricted by a low theoretical capacity (LiC 6 : 372 mAh g À 1 ) and inferior rate performances and therefore difficult to satisfy the ever-increasing needs of energy storage though already commercialized.…”

Nanocaging Silicon Nanoparticles into a Porous Carbon Framework toward Enhanced Lithium‐Ion Storage

“…To date, a great deal of strategies, including nanostructuring, [ 12–16 ] conductive hybridization, [ 17–19 ] and binder stabilization, [ 20–23 ] have been proposed to develop advanced Si‐based anodes with outstanding performance. In particular, hybridization with conductive materials, such as carbon, has been considered to be a promising route.…”

“…[8] Given these fatal shortcomings, rational exploration of efficacious design and synthesis strategies is highly desirable. [9][10][11] To date, a great deal of strategies, including nanostructuring, [12][13][14][15][16] conductive hybridization, [17][18][19] and binder stabilization, [20][21][22][23] have been proposed to develop advanced Si-based anodes with outstanding performance. In particular, hybridization with conductive materials, such as carbon, has been considered to be a promising route.…”