Abstract: Few-layer Ti3C2Tx nanosheets are successfully obtained by etching Ti3AlC2 with lithium fluoride and hydrochloric acid, and loaded on commercial PE separator through vacuum filtration to obtain a Ti3C2Tx modified lamellar permselective PE separator with a modification layer thickness of around 710 nm.Through sieving polysulfides and Li+ ion by layer spacing, the obtained separator can effectively suppress the diffusion of polysulfides to pass through the separator but show low hinderance to Li+ ion.It is shown through experiments that the Li-S battery with permselective Ti3C2Tx layer modified separator displays an improved cycle performance, which shows an initial specific capacity of 750.3 mAh·g-1 at 1 C rate and still maintains at 481.3 mAh·g-1 after 200 cycles, corresponding to a high capacity retention rate of 64.15%.
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