Despite their high theoretical energy density and low cost, lithium–sulfur batteries (LSBs) suffer from poor cycle life and low energy efficiency owing to the polysulfides shuttle and the electronic insulating nature of sulfur. Conductivity and polarity are two critical parameters for the search of optimal sulfur host materials. However, their role in immobilizing polysulfides and enhancing redox kinetics for long‐life LSBs are not fully understood. This work has conducted an evaluation on the role of polarity over conductivity by using a polar but nonconductive platelet ordered mesoporous silica (pOMS) and its replica platelet ordered mesoporous carbon (pOMC), which is conductive but nonpolar. It is found that the polar pOMS/S cathode with a sulfur mass fraction of 80 wt% demonstrates outstanding long‐term cycle stability for 2000 cycles even at a high current density of 2C. Furthermore, the pOMS/S cathode with a high sulfur loading of 6.5 mg cm−2 illustrates high areal and volumetric capacities with high capacity retention. Complementary physical and electrochemical probes clearly show that surface polarity and structure are more dominant factors for sulfur utilization efficiency and long‐life, while the conductivity can be compensated by the conductive agent involved as a required electrode material during electrode preparation. The present findings shed new light on the design principles of sulfur hosts towards long‐life and highly efficient LSBs.

The amount of Fe and NH3 treatment significantly affect the structural and catalytic properties of resulting ZIF-derived Fe–N–C catalysts.

The development of electrocatalysts from inexpensive, natural sources has been an attractive subject owing to economic, environmental, sustainable, and social merits. Herein, Fe-treated heteroatoms (N, P, and S)-doped porous carbons are synthesized for the first time by pyrolysis of bio-char derived from abundant human urine waste as a single precursor for carbon and heteroatoms, using iron(III) acetylacetonate as an external Fe precursor, followed by acid leaching and activation with a second pyrolysis step in NH 3 . In particular, the sample prepared at a pyrolysis temperature of 800 8C (FeP-NSC-800) contains iron phosphide (FeP, Fe 2 P) in the high-porosity heteroatoms-doped carbon framework along with Fe traces, and exhibits excellent oxygen reduction reaction (ORR) activity and stability in both alkaline and acidic electrolytes as demonstrated in half-and single-cell tests. Such excellent ORR catalytic performance is ascribed to a synergistic effect of not only multiple active FeÀP, FeÀN, and pyridinic and graphitic N species in the electrocatalyst but also facile transport channels provided by its hierarchical porous structure with micro-/mesopores. In addition, the sample exhibits high long-term durability and methanol crossover resistance.

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