Si–Mn/Reduced Graphene Oxide Nanocomposite Anodes with Enhanced Capacity and Stability for Lithium-Ion Batteries

Abstract

Although Si is a promising high-capacity anode material for Li-ion batteries (LIB), it suffers from capacity fading due to excessively large volumetric changes upon Li insertion. Nanocarbon materials have been used to enhance the cyclic stability of LIB anodes, but they have an inherently low specific capacity. To address these issues, we present a novel ternary nanocomposite of Si, Mn, and reduced graphene oxide (rGO) for LIB anodes, in which the Si-Mn alloy offers high capacity characteristics and embedded rGO nanosheets confer structural stability. Si-Mn/rGO ternary nanocomposites were synthesized by mechanical complexation and subsequent thermal reduction of mixtures of Si nanoparticles, MnO2 nanorods, and rGO nanosheets. Resulting ternary nanocomposite anodes displayed a specific capacity of 600 mAh/g with ∼90% capacity retention after 50 cycles at a current density of 100 mA/g. The enhanced performance is attributed to facilitated Li-ion reactions with the MnSi alloy phase and the formation of a structurally reinforced electroconductive matrix of rGO nanosheets. The ternary nanocomposite design paradigm presented in this study can be exploited for the development of high-capacity and long-life anode materials for versatile LIB applications.

Ultrathin supercapacitor electrodes with high volumetric capacitance and stability using direct covalent-bonding between pseudocapacitive nanoparticles and conducting materials

“…Therefore, recent research efforts have been directed toward the fabrication of various high-performance batteries [1][2][3][4][5], fuel cells [6][7][8], and electrochemical capacitors [9][10][11][12]. Notably, electrochemical capacitors, which are also called supercapacitors, can provide higher power and exhibit longer lifespans but less energy than lithium-ion batteries and therefore have become important energy storage devices for high-power applications, such as the load leveling of heavy machinery, backup power supplies and integrated power supplies for on-chip micro-scale devices [13][14][15][16][17][18][19][20].…”

In SituGeneration of Silicon Oxycarbide Phases on Reduced Graphene Oxide for Li-Ion Battery Anode

“…At the first discharge cycle, a continuous and sharp decrease in the potential from 3.4 V to 1 V with a successive lower decreasing rate from 1 V to 0.1 V implies the discharging saturation attained from the formation of solid-electrolyte interphase (SEI) and less stable LiÀSi. [13] The specific capacity of the electrode is almost 1.5 times of commercially used graphite and exhibits good capacity retention. Figure 2b shows that the reversible specific capacity of SiOC/rGO composite is about 507 mAhg À 1 with a columbic efficiency of 90.4 % untill the 50th cycle under a current density of 100 mAg À 1 .…”

Graphene‐Containing Nanomaterials for Lithium‐Ion Batteries

“…The resulting binary nanocomposite anodes displayed a specifi c capacity of 600 mAh g −1 after 50 cycles at a current density of 100 mA g −1 . [ 125 ] Ni-doped graphene-containing Si was produced by electrospinning, followed by thermal reduction. It possessed a specifi c capacity of 1045 mAh g −1 after 50 cycles at a current density of 100 mA g −1 and an enhanced rate capacity of 600 mAh g −1 at 1 A g −1 after 70 cycles.…”

“…Ni@graphene nanostructures solvothermal/heat treatment 1000 490 490 mAh g −1 at 5 A g −1 ( n = 1700) [92] Si-Mn/rGO mechanical/thermal reduction 100 668 90% ( n = 50) [125] Si-Ni-graphene electrospinning/thermal treatment 1000 740 81% ( n = 70) [126] (13 of 40) 1500400 wileyonlinelibrary.com…”

“…Si–Mn/rGO binary nanocomposites were yielded by mechanical complexation and subsequent thermal reduction of the mixtures of Si nanoparticles, MnO 2 nanorods, and rGO nanosheets. The resulting binary nanocomposite anodes displayed a specific capacity of 600 mAh g −1 after 50 cycles at a current density of 100 mA g −1 . Ni‐doped graphene‐containing Si was produced by electrospinning, followed by thermal reduction.…”