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Abstract Nanostructure CuFe 2 O 4 /CuO composites are synthesized via a precipitation method with different surfactants mediated Prussian blue analogues (PBAs) as precursors and following calcination in air. Comparatively, P-CuFe 2 O 4 /CuO (synthesized with PVP) and graphene oxide (GO) are hydrothermal processed to obtain P-CuFe 2 O 4 /CuO/reduced-GO. The PBAs precursors present as small spherical particles with PVP (P-CuPB), irregular polygon blocks with SDBS (S-CuPB) and CTAB (C-CuPB). Porous CuFe 2 O 4 /CuO with different size are obtained after calcining the PBAs and employed as anode of lithium ion batteries. The P-CuFe 2 O 4 /CuO exhibits an excellent capacity of 630.5 mAh g−1 with coulombic efficiency (CE) above 97%, which are better than the other two samples, and P-CuFe 2 O 4 /CuO/R-GO shows further improved reversible and stable capacity of 720 mAh g−1 with CE above 99% cycled at 500 mA g−1 even after 300 times. The results imply that surfactants can influence the particle structure and lithium storage performance. Besides, R-GO can effectively increase lithium ions insertion/de-insertion kinetics by supplying the matrix and buffer cushion for metal oxide volume changing during cycling. Graphical abstract Image 1 Highlights • Nanostructured CuFe 2 O 4 /CuO mediated by PBAs with different surfactants are obtained. • A simple soft-template synthesis mechanism was proposed. • CuFe 2 O 4 /CuO anode synthesized by PVP exhibited better lithium storage performance. • CuFe 2 O 4 /CuO/R-GO anode shown 720 mAh g−1 at 0.5 A g−1 even after 300 cycles. [ABSTRACT FROM AUTHOR]

Developing environment friendly and low cost methods of fabricating advanced anode materials for lithium ion batteries (LIBs) is very important. Using nori as the precursor, we designed and synthesized the composite of nitrogen-phosphorus-codoped carbon matrixes and cobaltic oxide nanoparticles (N, P-codoped C/Co 3 O 4 ) via hydrolysis of CoCl 2 and calcination method. It is interested that the nori not only provided the dopant of N and P elements but also formed the sponge-like porous carbon matrices which exhibited a large specific surface area as 246.4 m 2 g −1 . Both the dopants and the 3D porous carbon matrix are significantly helpful in improving the electrochemical performance of the product. Used as the anode material of LIB, N, P-codoped C/Co 3 O 4 offered a high reversible specific capacity of 927 mA h g −1 (the theoretical capacity of Co 3 O 4 is 890 mA h g −1 ) after 100 cycles at the current density of 100 mA g −1 and a good rate capability of 454 mA h g −1 at the current density of 1 A g −1 . Thus it is a promising alternative advanced anode material for LIB. In addition, the whole process is green, simple, economical and scalable and the method may be applied to synthesize other N, P-codoped carbon based composites. [ABSTRACT FROM AUTHOR]

FeMnO 3 /Mn 2 O 3 hybrids were prepared by calcinating the Mn 3 [Fe(CN) 6 ] 2 · n H 2 O Prussian Blue Analogues (PBAs) precursor, which involving a room-temperature precipitation of Mn 2+ and K 3 Fe(CN) 6 with or without citric acid as additives. The as-prepared FeMnO 3 inherits the morphology of PBAs and shows a porous structure due to releasing of CO 2 and NO 2 gases in the calcination process in air. FeMnO 3 nanocubes fulling of larger pores mixed with a new morphology of Mn 2 O 3 nanotubes are formed due to the assistance of citric acid (Sample Fe x Mn 2- x O 3 -C). While the single morphology of FeMnO 3 and Mn 2 O 3 nanocubes are obtained without citric acid (Sample Fe x Mn 2- x O 3 ). The Fe x Mn 2-x O 3 -C anode exhibits super Li + storage performance than that of Fe x Mn 2-x O 3 anode, such as higher initial discharge/charge capacities of 1580 and 850 mAh g −1 , and maintain 995 mAh g −1 until 170 cycles at a current density of 200 mA g −1 . The enhanced electrochemical performance is attributed to the inter-connected porous structure and large amount of mesopores of FeMnO 3 nanocubes and Mn 2 O 3 nanotubes, which effectively improved structure stability, reduced the diffusion length of lithium ions and electrons, increased the diffusion coefficient of Li + ion throughout the electrode, and buffered volume expansion during the Li + insertion/extraction processes. These results indicate that the porous FeMnO 3 nanocubes/Mn 2 O 3 nanotubes hybrids can be a promising anode material for high-performance LIBs. [ABSTRACT FROM AUTHOR]

Lithium metal anode with unparalleled theoretical specific capacity, ultra-low redox potential is a magic weapon to further enhance the energy density of the rechargeable batteries. Unfortunately, fragile solid electrolyte interphase, notorious dendritic growth and infinite volume expansion seriously hindered its commercialization process. Herein, a dendrite-free 3D SnCu scaffold is obtained by a simple, flexible replacement reaction. The porous SnCu with ordered layered structure can induce uniform Li deposition, suppress dendrites growth by reducing the local current density. What's more, the introduction of metal Sn enhance the lithiophilicity of Cu substrate, therefore decreasing the Li nucleation overpotential. Compared with planar Cu foil scaffold, the synthesized 3D SnCu current collector with dendrite-free morphology significantly improve the electrochemical performance of anode. The as-prepared SnCu scaffold obtains a highly Coulombic Efficiency of 94.2 % after 250 h in half-cells, and symmetrical Li@ 3D Sn/Cu cells exhibit stable cyclic for more than 1000 h at different current density (1and 5 mAh cm−2). • The 3D SnCu scaffold with lithiophilic site is prepared by a facile in-situ replacement method. • The 3D SnCu scaffold is porous and has a multi-layered structure. • A dendrite-free anode is obtained, and the symmetric cell has overlength lifespan under different capacity. • The electrochemical performance in full cell is improved. [ABSTRACT FROM AUTHOR]