Polypyrrole Coated Al-TDC Composite Structure as Lithium-Sulfur Batteries Cathode

Due to the high theoretical capacity of sulfur (1675[Formula: see text]mAh[Formula: see text][Formula: see text], low cost and environmental friendliness, lithium-sulfur batteries have shown broad prospects in future energy conversion and storage systems. However, the shuttle effect and insulating properties of sulfur restrict its practical application. Herein, we report a facile approach to fabricate Al-TDC@S-PPy composite material as lithium-sulfur battery electrode. In this strategy, a topological porous Al-TDC ([Formula: see text],5-thiophenedicarboxylate) with 8-connected clusters is reported, which can provide strong adsorption for dissolved intermediate polysulfides and alleviate volume expansion. Meanwhile, Polypyrrole, (PPy) as a conductive and flexible additive to expedite electron transport, improves electrical conductivity. Consequently, the Al-TDC@S-PPy composite cathode exhibits a higher initial specific capacity (1310.4[Formula: see text]mAh[Formula: see text][Formula: see text] at 0.2[Formula: see text]C). The final reversible capacity is 411.0[Formula: see text]mAh[Formula: see text][Formula: see text] after 200 cycles at 1 C. We can extend this strategy to other metal-organic frameworks (MOFs) and manufacture MOF/conductive polymer composite electrodes for high-performance lithium-sulfur batteries.