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Great efforts have been made to optimize Li metal anodes to improve energy density and cycle life. However, challenges remain in achieving uniform Li plating/stripping while maintaining stable interphase chemistry. Here, an engineered graphene aerogel with uniformly oriented microscale channels, and normalized lithiophilic binding sites as hosted Li anodes is reported. Vertically aligned graphene with oriented channels are constructed using a freeze-drying mechanism, and highly lithiophilic binding sites are optimized by adjusting functional oxygen anions on graphene. Based on the in-situ optical microscopy visualization and first-principles calculations, this graphene host design presents homogeneous Li-ion nucleation owing to its straight transport channels with ultrahigh lithiophilicity, resulting in greatly improved cycling stability. Also, the flat and compatible electrode–electrolyte interphase facilitates smooth Li growth, thereby suppressing the formation of dendrites. Notably, the symmetric cells using the new composite anodes exhibit superior electrochemical reversibility over 500 cycles, with the patternable LiFePO4//Li@graphene pouch cells displaying outstanding cycling performance. This graphene-hosted Li anode thus demonstrates great potential for Li batteries.

The typical chemical co-precipitation method was adopted for the synthesis of ferroferric oxide nanoparticles assisted powdered activated carbon (FONP-PAC). The crystal structure, surface profile, and element composition were systematically investigated to reveal FONP-PAC’s structural characteristics and tetracycline (TC) adsorption mechanism. We found the formation of FONP distributed on the surface/pores/channels of PAC. The adsorption behavior was dramatically fast and could be described by Freundlich isotherm and Elovich kinetic models. The thermodynamics investigation indicated that the adsorption process was spontaneous endothermic reaction, which was mainly carried out via chemical sorption mechanism. Our research of the superior adsorption capacity of magnetically separable FONP-PAC for TC from aqueous solution proposed a feasible adsorbent instead of PAC for antibiotic wastewater, and the good regeneration ability of FONP-PAC provided the feasibility of its application in engineering.

Poor cycle performance and low coulombic efficiency are bottleneck problems that hinder the further development of lithium–sulfur (Li–S) batteries. In this study, vapor silica-supported S is prepared by using a facile impregnation method and applied as cathode for Li–S batteries. Results indicate that approximately 43.7% of S is loaded into polyporous vapor silica. The prepared material also displays excellent electrochemical performance. After 200 cycles at a current density of 1000 mA·g−1, a capacity of 710 mAh·g−1 with a reversible capacity retention rate of 85% with coulombic efficiency of 100% is obtained. At a large current density of 2000 mA·g−1, the capacity of 605 mAh·g−1 is maintained after 300 cycles. This material contributes impressive surface-controlled pseudocapacity and high Li ion diffusion coefficient, which helps obtain high capacity and good rate performance during cycles. These results suggest that the prepared vapor silica-supported S can meet the needs of next-generation long-life Li–S batteries.