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Urchin-like α-Fe 2 O 3 /MnO 2 hierarchical hollow composite microspheres have been synthesized by using carbon as sacrificial templates. By combining the advantages of Fe 2 O 3 with high electrical conductivity and MnO 2 with high theoretical capacity, the urchin-like α-Fe 2 O 3 /MnO 2 composites present better electrochemical performances as a lithium ion battery anode compared with α-Fe 2 O 3 hollow spheres and MnO 2 hollow spheres. The α-Fe 2 O 3 /MnO 2 composites exhibit high initial discharge capacity of 1531 mAhg −1 and excellent reversible capacity of 860 mAhg −1 after 150 cycles at 0.1Ag −1 . Furthermore, the composites retain a discharge capacity of 494 mAhg −1 after 500 cycles at 0.5 Ag −1 . The excellent performances may originate from reinforced structural stability, large surface area and good electrical conductivity. The urchin-like α-Fe 2 O 3 /MnO 2 composite material may serve as a potential anode material for lithium-ion battery. [ABSTRACT FROM AUTHOR]

Abstract: Metal oxides/MnO2 hierarchical hollow hybrid nanostructures have attracted significant attention because of their wide potential applications. However, the exploration of a general synthetic approach for fabricating hierarchical hollow hybrid nanostructures is still a great challenge. Herein, a “penetration‐carbonization and reduction‐coating–annealing” route is presented for the generalized synthesis of metal oxides/MnO2 hierarchical hollow hybrid spheres, including NiO/MnO2, Co3O4/MnO2, and CuO/MnO2. Because of the unique hierarchical hollow hybrid nanostructures, NiO/MnO2 nanomaterials possess a desirable capacity (1520 mA h g−1) and outstanding cyclic stability (909 mA h g−1 at the 200th cycle) as Li‐ion battery anode materials. The work reported herein can not only pave the way for the generalized synthetic strategy of metal oxides/MnO2 hierarchical hollow hybrid nanostructures, but also provide a promising application of NiO/MnO2 nanomaterials for Li‐ion battery anode. [ABSTRACT FROM AUTHOR]

In this work, the composite materials of Zn2SnO4/SnO2@Mn2O3 microboxes have been synthesized after the calcination of precursor Zn2SnO4/SnO2@MnCO3, which is prepared by using a simple hydrothermal process. Preliminary results of the electrochemical performances of Zn2SnO4/SnO2@Mn2O3 microboxes, Zn2SnO4/SnO2 microboxes, and Mn2O3 nanoparticles have been also reported. On the one hand, the robust ZTO/SnO2 hollow microboxes can not only buffer the volume variation, but also efficiently prevent the aggregation of Mn2O3 nanoparticles. On the other hand, Mn2O3 nanoparticles provide more active sites, owing to the nanostructures of Mn2O3, as well as consolidate the hollow cubic structure during the lithium insertion/extraction process. In virtue of the synergistic effects of Zn2SnO4/SnO2 and Mn2O3, the Zn2SnO4/SnO2@Mn2O3 microboxes exhibit a higher initial discharge capacity (1505.3 mAhg−1) as well as a better cycling performance (597.2 mAhg−1 after 100 cycles) and rate capacity compared to Zn2SnO4/SnO2 and Mn2O3. [ABSTRACT FROM AUTHOR]

A novel porous membrane of chemically modified polyvinyl butyral (mPVB), with improved thermal properties and chemical stability for lithium ion battery applications, is successfully synthesized by utilizing the chain extension reaction of the OH units from PVB. The porous mPVB membranes are obtained via the tape casting and phase inversion method. The corresponding gel polymer electrolyte (GPE) is achieved by immersing the as‐prepared membranes in the liquid electrolyte. The electrochemical performances of the GPE show that the mPVB membranes have the features of good uniformity, high porosity (≈90%), great thermal stability, and high mechanical strength. Moreover, the GPE exhibits good chemical stability, a wide electrochemical window, as well as high ionic conductivity (≈1.21 × 10−3 S cm−1). A test of a Li/GPE/LiFePO4 battery cell shows a capacity of 147.7 mAh g−1 and excellent cycling stability, demonstrating the great potential of the mPVB‐based GPE for lithium ion battery applications. Porous modified polyvinyl butyral (mPVB) membranes are successfully synthesized by using the tape casting and phase inversion method for lithium ion battery applications. The proposed membranes with improved thermal properties, good uniformity, high porosity (≈90%), high mechanical strength, and chemical stability based on this easy preparation method indicate their good engineering potential. [ABSTRACT FROM AUTHOR]

Multi-yolk-shell SnCo@N-doped carbon nanocages with controllable carbon shell thickness are well fabricated by a novel approach. The multi-yolk-shell SnCo@N-doped carbon nanocages form an enough void volume to compensate the volume expansion of SnCo nanoparticles during Li + insertion. To optimize the electrochemical properties, SnCo@N-doped carbon nanocages with controllable carbon shell thickness can be tailored by coating polydopamine (PDA) with various thicknesses on CoSn(OH) 6 hollow nanocubes in the second step of the synthesis process. Multi-yolk-shell SnCo@N-doped carbon nanocages with the optimized shell thickness exhibit a high initial discharge capacity (1025 mAhg −1 ) and remarkable cyclic stability (611 mAhg −1 after 100 cycles) as Li-ion batteries anode. This work may open a wonderful way for the rational design of alloy@carbon composites with tailorable structures for next-generation anode nanomaterials in Li-ion battery. [ABSTRACT FROM AUTHOR]

SnO 2 @C@MnO 2 hierarchical hollow hybrid nanospheres have been obtained by coating the MnO 2 nanosheet-based hierarchical shell on SnO 2 @C hollow nanospheres via a redox method. The hierarchical hollow hybrid nanospheres are composed of the SnO 2 internal layer with hollow nanostructures, the carbon interlayer and the MnO 2 hierarchical nanostructured external layer built from two dimensional nanosheets. SnO 2 @C@MnO 2 nanomaterials exhibit a large initial discharge capacity (1378 mAhg −1 ), extraordinary cyclic stability (644.5 mAhg −1 after 200 cycles) and rate capability as Li-ion battery anodes. The excellent properties may benefit from the rational design of hierarchical hollow hybrid nanostructures and the synergistic effects between the three layers of SnO 2 , carbon and MnO 2 . [ABSTRACT FROM AUTHOR]

With a theoretical specific capacity much higher than that of traditional graphite, silicon (Si) has been considered as a promising anode material for next-generation lithium ion batteries (LIBs). Unfortunately, its practical application has been severely limited by the drawback of drastic volume expansion. In this report, we demonstrate a facile way to prepare binder-free, conductive agent-free silicon/reduced graphene oxide composite (Si/rGO) anode on nickel foam via one-step hydrothermal method followed by a post-annealing process, which delivers extraordinary cyclability and rate performance. The reversible specific capacity of the composite anode retained over 1500 mAh/g at 2 A/g after 2500 cycles and over 600 mAh/g at 4 A/g after 2500 cycles. Especially at a reasonable high current density of 16 A/g, the Si/rGO anode still displayed a specific capacity of 500 mAh/g. [ABSTRACT FROM AUTHOR]

In this work, nickel silicate (Ni 3 Si 2 O 5 (OH) 4 ) hierarchical hollow cubes have been fabricated via a simple template method. In virtue of the hierarchical hollow structure and appropriate specific surface area, nickel silicate nanosheets-based hollow cubes exhibit improved lithium storage properties than those of silica hollow cubes. [ABSTRACT FROM AUTHOR]