Pulverization Control by Confining Fe₃O₄ Nanoparticles Individually into Macropores of Hollow Carbon Spheres for High-Performance Li-Ion Batteries

Abstract

In this article, double carbon shell hollow spheres which provide macropores (mC) for ultrasmall FeO nanoparticle (10-20 nm) encapsulation individually were first prepared (FeO@mC). The well-constructed FeO@mC electrode materials offer the feasibility to study the volume change, aggregation, and pulverization process of the active FeO nanoparticles for Li-ion storage in a confined space. FeO@mC exhibits excellent electrochemical performances and delivers a high capacity of 645 mA h g at 2 A g after 1000 cycles. Even at 10 A g or after 1000 cycles at 2 A g, the porous carbon structure was well maintained and no obvious aggregation and pulverization of the FeO nanoparticles was observed, although the volume of the active FeO particles was expanded to 40-60 nm compared to that of the original particles (10-20 nm). This can be due to the in situ embedment of one FeO nanoparticle into one macropore individually. The uniform dispersion and confinement of the FeO nanoparticles in the macropores of the carbon shell could effectively accommodate severe volume variations upon cycling and prevent self-aggregation and spreading out from the carbon shell during the expansion process of the nanoscale FeO particles, leading to improved capacity retention. Our work confirms the effectiveness for pulverization control by confining FeO nanoparticles individually into macropores to improve its Li-ion storage properties, providing a novel strategy for the design of new-structured anode materials for Li-ion batteries.

Self-Assembled Nanoparticle Supertubes as Robust Platform for Revealing Long-Term, Multiscale Lithiation Evolution

“…38,[44][45][46] While a number of mechanisms have been proposed to interpret the origin, the capacity reactivation is believed to be closely related to the structural evolution of electrode materials. 26,47,48 We note that while many groups have explored the lithiation-induced morphological transformation of Fe 3 O 4 , [49][50][51] the direct observation of the long-term evolution of individual Fe 3 O 4 NPs has been rarely reported.…”

Self-assembled multifunctional Fe3O4 hierarchical microspheres: high-efficiency lithium-ion battery materials and hydrogenation catalysts

“…Although the coprecipitation process is associated with advantages, such as its non-requirement of expensive precursor complexes, its good reproducibility, and ecofriendly reaction conditions, the sizes and morphologies of the products cannot be controlled without utilizing additives. Therefore, a precursor transformation method was developed to prepare Fe 3 O 4 MNSs with controllable morphologies and sizes [9][10][11][12]. Moreover, it is wellknown that the precursor transformation method requires two steps, namely the preparation of the precursors and the thermal transition in an inert atmosphere.…”

Constructing Hollow Ni0.2Co0.8S@rGO Composites at Low Temperature Conditions as Anode Material for Lithium‐Ion batteries

“…[1][2][3][4][5][6][7][8][9][10][11][12] So far, a great diversity of materials has been extensively researched as anode materials for LIBs, such as metal oxides, metal sulfides, and carbonaceous materials. [13][14][15][16][17][18] Among these materials, metal sulfides (such as TiS 2 , FeS 2 , SnS 2 , CoS 2 , MoS 2 , etc.) have been emerged as the advanced anode materials due to their rich redox chemistry and high theoretical capacity, as compared with the state-ofthe-art graphite.…”

“…Nowadays, lithium‐ion batteries have aroused enormous attention due to their environmental friendliness, memory‐less effect, and high energy density . So far, a great diversity of materials has been extensively researched as anode materials for LIBs, such as metal oxides, metal sulfides, and carbonaceous materials . Among these materials, metal sulfides (such as TiS 2 , FeS 2 , SnS 2 , CoS 2 , MoS 2 , etc.)…”