| High-performance Li-ion batteries get wider and wider application in the world and have became one of the most promising power sources to meet the increasing need for the fast development of electric vehicles, solar, wind, smart grid, other energy store and conversion devices. There is a great interest in developing novel anode materials as a key part of Li-ion batteries. Co, Fe, Mo-based metal oxides (MOs) have attracted considerable interest for LIBs due to its high theoretic capacity, low cost and availability, which are typically2-3times higher than those of the graphite/carbonbased electrode materials. Furthermore, the presence of multiple valences of the cations in such spinel MOs systems is helpful to obtain the desirable nano/micro-structures. However, the major drawbacks of this class of materials are low electrical conductivity and the severe electrode pulverization caused by the drastic volumetric changes during repeated electrochemical cycling, and thus leads to rapid deterioration in capacity. Therefore, We intends to explore morphology-controlled and micro-order hollow Co, Fe, Mo-based metal oxides nanomaterials with multilevel interior structures by using green synthetic strategy of the self-assembly templates, derived by NMOFs and free-templates in order to further improve its electrochemical performance. Meanwhile the contolled synthesis mechanism of the desired materials is also discussed. Futhermore, electrochemical performance, synthesis conditions, components, morphology, structure and and different electrochemical analysis methods are used to study the electrocheical reaction mechanism of the prepared Co, Fe, Mo-based metal oxide materials. Our efforts will provide experimental foundation and theoretical basis for MTMOs anodic materias of Li-ion batteriThe simultaneous coordinating etching and precipitating reaction is employed to prepare hollow crossed NiCo2O4nanocubes as anode materials for Li-ion batteries. Amorphous hollow (NiCox)O(OH) nanoboxes form uniformly firstly, and the subsequent calcination results in the formation of NiCo2O4nanocubes. It exhibits a stable reversible capacity of1160mA·h g-1at constant current density of200mA g’1, and capacity retention keeps over91.1%after200cycles. The unique hollow structure can shorten the length of Li-ion diffusion, which is benefit for the rate performance. Furthermore, the hollow structure offers a sufficient void space, which sufficiently alleviates the mechanical stress caused by volume change. Additionally, the multi-elements characteristics of active materials allow the volume change to take place in a stepwise manner. Therefore, the hollow crossed NiCo2O4nanocube electrode exhibits excellent electrochemical performance. This strategy method is simple, low cost, which may shed light on a new avenue for fast synthesis of hollow crossed structural nano functional materials for energy storage, catalyst, sensor and other new applications.Hollow porous CoFe2O4nanocubes from metal-organic frameworks are fabricated through a general facile strategy. The intrinsic hollow nanostructure can shorten the lengths for both electronic and ionic transport, enlarge the surface areas of electrodes, and the improve accommodation of the volume change during Li insertion/extraction cycling. The hybrid multi-elements characteristics allow the volume change to take place in a stepwise manner during electrochemical cycle. Therefore, as-prepared CoFe2O4electrode exhibits outstanding performance as anode materials for lithium ion batteries. The stable capacity arrives at815mA-h g"1for20C. Subsequently, a specific capacity of ca.1043mA-h g"1is recovered when the current rate reduces back to1C after200cycles. This general strategy may shed light on a new avenue for large-scale synthesis of hollow porous hybrid nanocubes via MOFs for energy storage, environmental remediation and other novel applications.Alcoholysis is employed to prepare cage-bell α-MoO3-SnO2hybrid nanoparticle aggregates as anode materials for Li-ion batteries. Amorphous carbon can be loaded on the α-MoO3-SnO2nanoparticles uniformly in the solvothermal alcoholysis process, and the subsequent calcination results of the formation of hollow cage-bell structures. It exhibits a stable reversible capacity of865mA·h g-1at constant current density of200mA g-1, and capacity retention keeps over93.1%after200cycles. The unique hollow structures can shorten the length of Li-ion diffusion, which is benefit for the rate performance. Furthermore, the hollow structure offers a sufficient void space, which sufficiently alleviates the mechanical stress caused by volume change. Additionally, the multi-elements characteristics of active materials allow the volume change to take place in a stepwise manner. Therefore, the hollow α-MoO3-SnO2hybrid electrode exhibits excellent electrochemical performance. This method is simple, low cost, mass-productive, and can also be used to prepare other advanced functional materials. |
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