Search

[Display omitted] • 3D Janus face graphene (JFG) substrate is prepared in large scale by facile process. • Distinct Janus face comes from different aperture size and N-doping on both sides. • Dendrite growth is suppressed when lithiophilic layer is as Li deposition interface. • Li@JFG composite anode achieves efficient Li electro-plating/stripping. • Li@JFG anode has high coulomb efficiency, small polarization and stable cycle. The dendrite growth and irreversibility of lithium (Li) metal anode seriously hinders the wide-scale application of high-energy–density rechargeable batteries. Here, we report a thin Janus-faced graphene substrate, consisting of lithiophilic-lithiophobic faces separately, for Li plating/stripping. The visualized analysis demonstrates that the unique Janus-faced graphene structure provides different lithiophilic sites and pore channels to steer the Li electrodeposition and suppress the dendrite growth. As expected, the Janus-faced graphene anode achieves long-term Li plating/stripping with high Coulombic efficiency, small polarization and stable cycling throughout the symmetry, asymmetry and LiFePO 4 full cells. Such an encouraging strategy for reversible Li plating/stripping provides a promising way to design long-life carbon-base anode materials for Li metal batteries. [ABSTRACT FROM AUTHOR]

Owing to the high theoretical specific capacity, transition metal selenides (TMSs) have emerged as promising anode materials for lithium-ion batteries (LIBs). However, the application of TMSs still confronts fast capacity decay and sluggish reaction kinetics associated to their inherent poor conductivity and huge volume expansion during lithiation-delithiation cycles. Herein, the fine ZnSe nanoparticles are implanted into N-doped porous carbon nanosheets through synchronous pyrolysis/selenization of a leaf-like zeolitic imidazolate framework mixed with selenium powder. The highly dispersed fine ZnSe nanoparticles (NPs) coupled with conductive porous carbon nanosheets (denoted as ZnSe/NC) endow the resultant composite with superior structural merits for facilitating electron/ion transfer, thus alleviating the volume fluctuation. The systematic electrochemical investigation illustrates that the as-prepared ZnSe/NC-700 electrode can obtain a high reversible capacity (426.5 mAh g−1 at 1 A g−1 after 1000 cycles), excellent cycling stability (368.9 mAh g−1 after 1800 cycles at 2 A g−1) and nearly 100％ columbic efficiency. In all, our strategy provides a new idea for synthesis of unique anode materials in LIBs. [Display omitted] • The fine ZnSe nanoparticles/N-doped porous carbon nanosheets (ZnSe/NC-700) are synthesized. • The ZnSe/NC-700 can be obtained through synchronous pyrolysis/selenization. • The ZnSe/NC-700 delivers a high reversible capacity and excellent cycling stability. • Kinetics analysis verifies the pseudocapacitive behavior of the ZnSe/NC-700. [ABSTRACT FROM AUTHOR]