Silicon Inverse‐Opal‐Based Macroporous Materials as Negative Electrodes for Lithium Ion Batteries

Abstract

Several types of silicon‐based inverse‐opal films are synthesized, characterized by a range of experimental techniques, and studied in terms of electrochemical performance. Amorphous silicon inverse opals are fabricated via chemical vapor deposition. Galvanostatic cycling demonstrates that these materials possess high capacities and reasonable capacity retentions. Amorphous silicon inverse opals perform unsatisfactorily at high rates due to the low conductivity of silicon. The conductivity of silicon inverse opals can be improved by their crystallization. Nanocrystalline silicon inverse opals demonstrate much better rate capabilities but the capacities fade to zero after several cycles. Silicon–carbon composite inverse‐opal materials are synthesized by depositing a thin layer of carbon via pyrolysis of a sucrose‐based precursor onto the silicon inverse opals. The amount of carbon deposited proves to be insufficient to stabilize the structures and silicon–carbon composites demonstrate unsatisfactory electrochemical behavior. Carbon inverse opals are coated with amorphous silicon producing another type of macroporous composite. These electrodes demonstrate significant improvement both in capacity retentions and in rate capabilities. The inner carbon matrix not only increases the material conductivity but also results in lower silicon pulverization during cycling.

K0.25Mn2O4nanofiber microclusters as high power cathode materials for rechargeable lithium batteries

“…Similar effects have been observed previously. [39][40][41] The reason for such a phenomenon is 25 not exactly clear; however, it can be conjectured that some sort of local restructuring or 'activation' takes place in the material during the initial lithium intercalation. Fig.…”

A colloidoscope of colloid-based porous materials and their uses

“…68,74,419,427 Swelling and shrinking can lead to loss of structural integrity and battery failure. Several groups have investigated using inverse opals to avoid this degradation, especially for MnO 2 465 and MnSiO 4 464 positive electrodes and silicon negative electrodes 74,419,425,427 in Li-ion batteries, as well as for sulfur in Li-S batteries. 68 These studies describe hierarchical structures, where a conducting matrix is covered with an active material.…”

“…26,62,427 High charging and discharging rates stem from the high surface area and short distance between the active area and the conducting support. With limited tortuosity, ion diffusion is facile and controllable, with the added benefit of being able to undergo volume changes without loss of structural integrity.…”

Materials by design: Using architecture in material design to reach new property spaces

“…81 , 82 (For more information on lithium-ion batteries, see the article in this issue by Crabtree et al) Esmanski and Ozin 81 and Pikul et al 83 extensively explored silicon inverse opals ( Figure 6 ), and Xia and co-workers 82 fabricated silicon nanolattices to study how macroporosity and architecture aid in accommodating the dramatic volume swings experienced by the silicon electrode as a result of lithium intercalation during cycling. 81 The introduction of 3D architecture into silicon electrodes promises M many advantages, including enhanced mechanical stability, minimal lithium diffusion distances and large surface areas for improved charge and discharge rate, control over porosity for superior electrolyte infi ltration and increased cell capacity, and better electrical conductivity than can be obtained with electrodes based on particle aggregates requiring binders and additives. 81 , 82 …”