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A novel one-dimensional CoMnO x /N-CNT composite was synthesized by binding Mn-Co nanoparticles on nitrogen doped carbon nanotubes (N-CNT) through solvothermal method and followed by high temperature pyrolysis. The as-made Mn-Co/N-CNT as LIBs anode material exhibits excellent rechargeable capability, i.e. 1028 mAh·g −1 at 200 mA·g −1 . Doped nitrogen on CNT effectively increase the conductivity of the complex and the binding energy between Mn-Co nanoparticles and CNT, which lead to more stable and higher conductive complex during charge/discharge cycling process. [ABSTRACT FROM AUTHOR]

[Display omitted] • CoTe 2 -ZnTe confined on MOF-derived skeleton (CoZn-Te/NC) shows abundant interfaces. • High conductivity and fast transfer kinetics are achieved in CoZn-Te/NC composites. • The conversion and alloy reaction coexist in CoZn-Te/NC composites. • The effects of heterostructure and N -doping boost the sodium storage performance. Two-phase or multiphase engineering is contributed to realizing rapid electron/ion transfer kinetics for transition metal tellurides in sodium-ion batteries (SIBs). However, the large volume variation and fundamental storage mechanism of these materials remain unsolved. Herein, petal-like N -doped carbon-confined CoTe 2 -ZnTe heterostructures (CoZn-Te/NC) are fabricated as anodes in SIBs via a facile bimetal-organic framework-derived strategy. Benefiting from the abundant phase interfaces and dual-defective sites, CoZn-Te/NC composites have fast electrons/ions diffusion and superior pseudocapacitive property. Particularly, introducing a petal-like nitrogen-doped carbon inhibits the particle agglomeration and alleviates volume expansion, thus improving structural stability during cycling. The CoZn-Te/NC exhibits a superior rate capacity of 106 mAh/g at 10 A g−1 and a high reversible capacity of 150 mAh/g at 1.0 A g−1 over 600 long-term cycles. The unique conversion and alloying/de-alloying reaction mechanisms of CoZn-Te/NC are revealed by the in-situ and ex-situ techniques. This work gives promising insights for designing high-performance electrode materials by phase interface, doping, and confining strategy. [ABSTRACT FROM AUTHOR]

• The formation of Co-N bond in hybrid catalyst can effectively enhance interfacial charge transfer. • Enhanced oxygen catalytic activity using NCNTs/Ni offers excellent electrical conductivity. • The CoS x /NCNTs/Ni exhibits outstanding ORR/OER performance and realizes the potential for application on zinc-air batteries. The slow kinetics of the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) remain the primary problem impeding the commercialization of zinc-air batteries (ZABs). Herein, we demonstrate a hybrid composite consisting of multivalent CoS x nanoparticles and nitrogen-doped carbon nanotubes catalytically active-nickel (NCNTs/Ni) as an advanced ORR/OER electrocatalyst with excellent electrocatalytic activity. The Co-N bonds in the hybrid catalyst effectively enhance interfacial charge transfer, resulting in synergetic effects for enhanced oxygen electrochemistry. The optimized hybrid, CoS x /NCNTs/Ni-2, affords excellent performance in an alkaline ZAB, achieving a high-power density of 131 mW cm−2, and the voltage gap remained at only 0.87 V after 200 h of continuous charge–discharge at 5 mA cm−2. This study provides a facile strategy for the construction of bifunctional hybrids with non-precious metals for potential application in ZABs and other sustainable energy conversion devices. [ABSTRACT FROM AUTHOR]