A hybrid structure consisting of boron-doped porous carbon spheres and graphene (BPCS-G) has been designed and synthesized toward solving the polysulfide-shuttle problem, which is the most critical issue of current Li-S batteries. The proposed hybrid structure showing high surface area (870 m²·g⁻¹) and high B-dopant content (6.51 wt.%) simultaneously offers both physical confinement and chemical absorption of polysulfides. On one hand, the abundant-pore structure ensures high sulfur loading, facilitates fast charge transfer, and restrains polysulfide migration during cycling. On the other hand, our density functional theory calculations demonstrate that the B dopant is capable of chemically binding polysulfides. As a consequence of such dual polysulfide confinement, the BPCS-G/S cathode prepared with 70 wt.% sulfur loading presents a high reversible capacity of 1,174 mAh·g⁻¹ at 0.02 C, a high rate capacity of 396 mAh·g⁻¹ at 5 C, and good cyclability over 500 cycles with only 0.05% capacity decay per cycle. The present work provides an efficient and cost-effective platform for the scalable synthesis of high-performance carbon-based materials for advanced Li-S batteries.

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设计并合成了由掺硼多孔碳球和石墨烯（BPCS-G）组成的混合结构，以解决多硫化物穿梭问题，这是当前Li-S电池最关键的问题。拟议的混合结构显示出高表面积（870 m ² ·g ^-1）和高B掺杂剂含量（6.51 wt。％）同时提供了多硫化物的物理限制和化学吸收。一方面，丰富的孔结构可确保高硫负载，促进快速电荷转移，并抑制多硫化物在循环过程中的迁移。另一方面，我们的密度泛函理论计算表明，B掺杂剂能够化学键合多硫化物。作为这种双多硫化物限制的结果，BPCS-G / S阴极，用70重量％的硫负载礼物制备1174毫安时的高可逆容量·克^-1 0.02 C，396毫安·g的高倍率容量^{- 1个}在5 C下保持良好的循环能力，并且在500个循环中具有良好的循环能力，每个循环的容量衰减仅为0.05％。本工作为可扩展合成高级Li-S电池的高性能碳基材料提供了一个高效且具有成本效益的平台。

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