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The CuF 2 @CoPPc lamellar hybrid was prepared by the recrystallization of CoPPc on the surface of CuF 2. This configuration can efficiently prevent CuF 2 from contacting directly with electrolyte and improve the reaction activity by weakening the bonding strength of Cu-F. CoPPc can catalyze the invertibility and surface reaction of CuF 2 , resulting in long cyclability, high capacity and high reversibility. [Display omitted] • A new strategy of tailoring the intrinsic Cu-F bond strength of CuF 2 is introduced to improve its durable reversibility. • As a catalyst, CoPPc enhances and improves the reversibility and surface reaction of CuF 2. • The synergistic effect of CuF 2 and CoPPc drastically promotes the charge transfer kinetics of the composite. • CuF 2 @CoPPc has long cyclability, high capacity and high reversibility. CuF 2 is a promising candidate of electrode materials for lithium-ion batteries due to its high specific capacity, high power density and environmental friendliness. However, the irreversible phase conversion and sluggish kinetics caused by serious copper dissolution and low conductivity make CuF 2 difficult to achieve long cycling life. A facile strategy to incorporate CoPPc into CuF 2 was proposed firstly to regulate the Cu-F bonding force to realize the high reversibility of CuF 2 for lithium-ion storage. The results of DFT calculation, differential charge density simulation, work function calculation and COHP bond level calculation show that the existence of CoPPc can improve the surface charge distribution of CuF 2 and thus improve the reversibility for durable lithium-ion storage. The cycle life performance of the CuF 2 @CoPPc composite electrode obtained by this method reached staggering 500 cycles and the capacity remained at 594.8 mAh/g. [ABSTRACT FROM AUTHOR]

[Display omitted] • CoPPc@SnO 2 hybrid with high-compact mechanical interface was successfully prepared. • Outstanding interface pseudo-capacitive effect was triggered. • Extra Li-ion interface storage capability has been demonstrated. • The kinetics is enhanced due to improved pseudo-capacitive effect. Extra interface capacity derived from the surface pseudo-capacitive effect has been widely reported and considered an important role in enhancing excellent kinetics in the system of transition metal oxides. However, outstanding pseudo-capacitive effect is seldom found in other kind of oxides or systems. In this work, we strategically use cobalt phthalocyanine decorated tin oxide nanotubes to fabricate CoPPc@SnO 2 amorphous/polycrystalline composite with enhanced extra lithium-ion storage capability. Amazing interface Li-ion storage in the configured CoPPc@SnO 2 is successfully triggered, and outstanding pseudo-capacitive effect is demonstrated as an important factor to improve the overall capacity as well as kinetics of the composite electrode. The reversible capacity of CoPPc@SnO 2 could be maintained to 950 mA h g−1 after 400 cycles, comparing with 500 mA h g−1of CoPPc and 250 mA h g−1 of SnO 2 under the same conditions. [ABSTRACT FROM AUTHOR]

The MnO/C@CoPPc composite is prepared by facile surface-vacancy filling engineering. CoPPc is strategically impregnated into the empty space among the needles of MnO/C and simultaneously coated on the surface of MnO/C micro-rods. This structure not only guarantee the active center of MnO/C from the direct contact with electrolytes, but also efficiently alleviate its conductive disconnection on cycling. The presence of CoPPc can also effectively inhibit the volume expansion of MnO. The MnO/C@CoPPc composite has high reversible capacity and high stability. [Display omitted] • CoPPc not only guarantee the active center of MnO/C from the direct contact with electrolytes, but also efficiently alleviate its conductive disconnection on cycling. • The configuration of CoPPc-impregnated MnO/C composite effectively improved the electrochemical performance of MnO/C. • CoPPc can effectively inhibit the volume expansion of MnO during the charge-discharge cycle. • The MnO/C@CoPPc composite has high capacity and high stability. MnO has the advantages of high theoretical capacity, abundant resources and environmental friendliness, which is a potential material for lithium-ion storage. However, severe volume expansion and sluggish kinetics make MnO difficult to maintain long-term stability. In this study, MnO/C@CoPPc micro-rods composed of coral-like MnO/C nanobundles coated with CoPPc was synthesized via facile method. CoPPc impregnated into the empty space and simultaneously coated on the surface of the needles of MnO/C functions as an elastic layer to accommodate the mechanical stress caused by volume expansion of MnO/C, and simultaneously function as a buffering layer to keep electric disconnection on cycling. The volume of MnO/C is dramatically suppressed from 370% to 120%, and the reversible capacity is improved. Therefore, the configured MnO/C@CoPPc exhibits a high stability and delivers a high reversible capacity of 679.6 mAh/g after 200 cycles. [ABSTRACT FROM AUTHOR]