Attapulgite and multiwalled carbon nanotubes co-integrated hierarchical porous polyacrylonitrile membrane as a multifunctional interlayer for lithium-sulfur batteries with enhanced performance

Abstract

• ATTP and MWCNTs co-integrated porous PAN membrane was first fabricated. • The membrane was investigated as a multifunctional interlayer for Li-S batteries. • A synergistic effect of ATTP and MWCNTs effectively suppress the shuttle effect. • The cell with such interlayer demonstrates superior cycling stability . As a kind of natural porous nanorods, attapulgites (ATTP) are widely used in many fields because of their high specific surface area, high porosity and strong adsorption ability. In this work, ATTP and multiwalled carbon nanotubes (MWCNTs) co-integrated polyacrylonitrile (PAN) hierarchical porous membrane (ATTP/CNTs@PAN) has been fabricated and investigated as a multifunctional interlayer for lithium-sulfur batteries. Due to a synergistic effect of ATTP and the carboxylated MWCNTs, the porous interlayer is able to effectively suppress the shuttle effect by trapping and confining the dissolved polysulfides. Meanwhile, the addition of MWCNTs improves the conductivity of the composite membrane, which is beneficial for the reutilization of the active species. Therefore, the cells with the interlayer demonstrates superior electrochemical performance, delivering a high initial discharge capacity of 1283 mAh g −1 at 0.2 C, and retaining 785 mAh g −1 after 300 cycles with a Coulombic efficiency exceeding 99%. Meaningfully, this porous composite membrane is low-cost and very effective for high performance Li-S batteries.