![]() ![]() ![]() For instance, Cui and coworkers reported hollow carbon nanospheres as Li hosts for stable Li plating and stripping. Advantages of high electronic conductivity, excellent mechanical and chemical stability, and low density additionally promote the potential of carbon materials as Li host candidates. Large surface area of 3D carbon materials significantly lowers the local current density to inhibit Li dendrites. In particular, three-dimensional carbon materials have drawn worldwide attentions as favorable Li hosts for dendrite-free Li metal anodes. Three-dimensional (3D) porous copper, fibrous Li 7B 6, and ZnO composites exhibit evident improvements to suppress the dendritic formation as Li hosts. Introducing a host material as a stable second phase to accommodate Li deposition offers a reasonable strategy to address the above hostless issues. The Li dentrites not only breed “dead Li” with fast capacity decay, but also raise potential safety hazards such as internal short circuit that hinders the practical applications of Li metal batteries. In addition, uneven Li deposition causes the formation of notorious Li dendrites. The morphology variation inevitably results in the crack/repair of solid electrolyte interphase (SEI) that continuously consumes the electrolyte and induces low Coulombic efficiency (CE). However, the electrochemistry of Li metal is intrinsically a hostless process with virtually infinite volume change and drastic morpholgy variation during Li plating and stripping. Lithium (Li) metal with an ultrahigh theoretical specific capacity of 3860 mAh g −1 and the lowest electrochemical potential of −3.040 V versus the standard hydrogen electrode constitutes a promising anode material to construct high-energy-density batteries. The ever growing demand of energy supply stimulates endless prusuit of high-performance energy storage devices. The favorable lithium nucleation mechanism on POF materials inspires further investigation of lithiophilic electrochemistry and development of lithium metal batteries. Consequently, POF-based anodes demonstrate superior electrochemical performances with high Coulombic efficiency over 98%, reduced average voltage hysteresis, and excellent stability for 300 cycles at 1.0 mA cm −2, 1.0 mAh cm −2 superior to both Cu and graphene anodes. The extraordinary lithiophilicity of POF even beyond lithium nuclei validated by DFT simulations and lithium nucleation overpotentials affords a novel mechanism of favorable lithium nucleation to facilitate uniform nucleation and inhibit dendrite growth. In this contribution, a framework porphyrin (POF) material with precisely constructed lithiophilic sites in regard to chemical structure and geometric position is employed as the lithium host to address the above issues for dendrite-free lithium metal anodes. Precise construction of lithiophilic sites with desired structure and homogeneous distribution significantly promotes the lithiophilicity of lithium hosts but remains a great challenge. Lithiophilic host materials are highly considered for achieving uniform lithium deposition. Lithium metal constitutes promising anode materials but suffers from dendrite growth. ![]()
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