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[Display omitted] • The Cl-doped ZIF-67-derived carbon microspheres were prepared by a novel chlorination method in high-temperature. • The electrochemical performance of CCH@CM has been greatly improved compared to ZIF-67. • CCH@CM continues the microporous structure of ZIF-67 while minimizes volume expansion. • Cobalt Chloride Hydrate (CCH) grown in situ provides maximum active sites for electrochemical reactions with Li-ions. In this work, the carbon-microsphere loaded with cobalt chloride hydrate (CCH@CM) was prepared via a collaborative and chlorination strategy derived from ZIF-67 precursor, which exhibits a superior electrochemical performance as a lithium-ion battery anode material. The synthesized CCH@CM obtained a high initial discharge capacity (947 mAh g−1) and the capacity attenuation rate is close to zero after 200 cycles at the current density of 100 mA g−1. The porous structure derived from ZIF-67 not only can provide a conductive path, which increases the transport of electrons and lithium ions, but also alleviate volume expansion. The presences of -Cl-/H 2 O groups provide active sites for the anchoring of Li+. As the first successful synthesizing the cobalt chloride hydrate (CCH) from ZIF-67, good electrochemical performance provides a promising for the large-scale application in lithium ion batteries. [ABSTRACT FROM AUTHOR]

[Display omitted] • Electrochemistry mechanism of Fe-based SMS in LIBs is elucidated. • Two potential adsorption sites of Fe-based SMS are obtained by DFT methods. • Adsorption sites are attractive for Li+ with the increasing of around electrons. • Large amounts of LiH are released to obtain good electrochemical performance. The Solid Molten Salt-Fe 2 O 3 @Polypyrrole (SMS-Fe 2 O 3 @PPy) materials as anode electrode are successfully synthesized by a two-step method and applied for lithium-ion batteries (LIBs). The SMS-Fe 2 O 3 @PPy electrode is composed of Fe-based solid molten salt (SMS), PPy and octahedral Fe 2 O 3 nanoparticles. Importantly, the introduction of PPy not only can provide a coating to suppress the volume expansion but also improve the electrical conductivity of the material. The elegant synergy effectively reduces the volume expansion of the material during the Li+ insertion/extraction process. As an anode for the LIBs, the SMS-Fe 2 O 3 @PPy electrode deliver reversible capacities of 1346 mAh/g at 100 mA g−1, good cycle stability of 1198 mAh/g even after 1000 cycles at 500 mA g−1 and excellent rate performance of 110 mAh/g even at 50 A g−1. It is found that the SMS can provide a large amount of LiH by combining with Li+ in the discharge process. The potential adsorption sites (site A and site B) from SMS were obtained by Density Functional theory (DFT) methods, and the attraction capacity of SMS to Li+ increased with the increasing of the number of electrons around SMS. All above unique advantages lead to a large specific capacity as well as excellent cycling stability, resulting in a considerable electrochemical performance. It can be seen from the excellent electrochemical performance of SMS-Fe 2 O 3 @PPy electrode that portends this will be a promising material for high-performance electrochemical devices. [ABSTRACT FROM AUTHOR]