Despite the great progress achieved, lithium-sulfur (Li-S) batteries still suffer unsatisfactory performance at high sulfur loading (>5 mg cm⁻²), which results from the impeded kinetics in charge transfer and polysulfides conversion with increasing electrode thickness. Herein, we have constructed a high-sulfur-loading monolithic cathode by in-situ reducing graphene oxide (GO) in the aqueous solution with dispersed sulfur-filled N,P dual-doped carbon nanocages (NPCNC). The Li-S battery with the areal sulfur loading of 6 mg cm⁻² exhibits a high areal capacity of 6.7 mAh cm⁻² and a retention of 4.2 mAh cm⁻² after 250 cycles. The excellent performance is attributed to the synergism of the facilitated charge transfer and alleviated polysulfide diffusion by the reduced GO-framed 3D network, and the suppressed shuttle and polarization effects by the confinement and electrocatalysis of NPCNC. In addition, the monolithic sulfur electrode is free from binder, conductive agent and current collector, much beneficial to gravimetric performance. This study demonstrates an efficient strategy to increase the areal performance of Li-S batteries.

尽管取得了很大的进步，但锂-硫（Li-S）电池在高硫负荷（> 5 mg cm ^-2）下仍表现出不令人满意的性能，这是由于电荷转移和多硫化物转化的动力学受阻，以及电极厚度的增加所致。本文中，我们通过用分散的硫填充的N，P双掺杂碳纳米笼（NPCNC）原位还原水溶液中的氧化石墨烯（GO）来构建高硫负载的整体阴极。面积硫负载为6 mg cm ^-2的Li-S电池具有6.7 mAh cm ^-2的高面积容量和4.2 mAh cm ^-2的保持力250个周期后。优异的性能归因于减少的GO框架3D网络促进了电荷转移和减轻了多硫化物扩散的协同作用，以及由于NPCNC的限制和电催化而抑制了穿梭和极化效应。此外，整体式硫电极不含粘合剂，导电剂和集电器，对重量分析性能非常有利。这项研究证明了提高Li-S电池表面性能的有效策略。