Single‐atom catalysts (SACs) pave new possibilities to improve the utilization efficiency of sulfur electrodes arising from polysulfide shuttle effects and sluggish kinetics due to their excellent applicability in atomic‐scale reaction… Click to show full abstract
Single‐atom catalysts (SACs) pave new possibilities to improve the utilization efficiency of sulfur electrodes arising from polysulfide shuttle effects and sluggish kinetics due to their excellent applicability in atomic‐scale reaction mechanisms and structure‐activity relationships. Herein, nitrogen (N)‐anchored SACs on the highly ordered N‐doped carbon nanotube arrays are reported as the sulfur host for fast redox conversion in lithium‐sulfur (Li‐S) batteries. The cube structure of the aligned carbon nanotubes can promote the rapid mass transfer under high sulfur loadings, and abundant single‐atom active sites further accelerate the conversion of lithium polysulfides (LiPSs). The synergistic enhancement effect induced by adjacent single atoms with interatomic distances <1 nm further accelerates the rapid multi‐step reaction of sulfur at high sulfur loadings. As a result, the obtained Li‐S batteries exhibit outstanding cycle stability with a high areal capacity of 5.6 mAh cm−2 after 100 cycles under a high sulfur loading of 7.2 mg cm−2 (electrolyte to sulfur ratio is ≈3.7 mL g−1). Even assembled into a pouch cell, it still delivers a high capacity of 953.4 mAh g−1 after 100 cycles at 0.1 C, contributing to the development of the practically viable Li‐S batteries.
               
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