Coordination competition-driven synthesis of triple-shell hollow α-Fe2O3 microspheres for lithium ion batteries

Design and synthesis of yolk-shell Fe2O3/N-doped carbon nanospindles with rich oxygen vacancies for robust lithium storage

Ferric oxide (Fe₂O₃) is an attractive anode material for lithium-ion batteries (LIBs) with a high theoretical capacity of 1005 mA h g^-1. However, its practical application is greatly restrained by the rapid capacity fading caused by the large volume expansion upon lithiation. To address this issue, we have designed and synthesized a unique yolk-shell Fe₂O₃/N-doped carbon hybrid structure (YS-Fe₂O₃@NC) with rich oxygen vacancies for robust lithium storage. The obtained results show that YS-Fe₂O₃@NC delivers a high reversible capacity of 578 mA h g^-1 after 300 cycles at a current density of 5 A g^-1, about 11 times that (53.7 mA h g^-1) of pristine Fe₂O₃. Furthermore, a high specific capacity of 300.5 mA h g^-1 even at 10 A g^-1 is achieved. The high reversible capacities, excellent rate capability and cycle stability of YS-Fe₂O₃@NC might be attributed to the elaborate yolk-shell nanoarchitecture. Moreover, electron percolation and a local built-in electric field induced by oxygen vacancies in the Fe₂O₃ matrix could also enhance the kinetics of Li⁺ insertion/deinsertion.

One-pot thermal decomposition of commercial organometallic salt to Fe2O3@C-N and MnO@C-N for lithium storage

Iron oxide (Fe2O3) nanoparticles encapsulated in the N-doped carbon framework (Fe2O3@C-N) were synthesized via a one-step thermal decomposition reaction of commercial C10H12FeN2NaO8 (ethylenediaminetetraacetic acid monosodium ferric salt), which can serve as the source of Fe, O, C, and N. As an anode material for lithium storage, the Fe2O3@C-N sample exhibits a reversible capacity of 1072 mA h g-1 after 200 cycles at 0.2 A g-1 and 553 mA h g-1 after 500 cycles at 0.5 A g-1. Furthermore, the synthetic strategy can be simply extended to prepare other similar products, e.g. MnO@C-N and ZnO@C-N. The MnO@C-N anode also shows good cycling performances (915 mA h g-1 after 200 cycles at 0.2 A g-1 and 768 mA h g-1 after 500 cycles at 0.5 A g-1).

Double-shell SnO2@Fe2O3 hollow spheres as a high-performance anode material for lithium-ion batteries

Construction of novel electrode materials is an effective way to enhance the electrochemical performance of lithium ion batteries (LIBs).