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Lithium-sulfur batteries (LSBs) have attracted widespread attention because of their advantages such as high discharge capacity and high energy density. Although LSBs have good development potential, there are still many obstacles, such as poor conductivity, volume expansion etc., especially shuttle effect which seriously limit the application of LSBs. To restrain the shuttle effect, we proposed a novel Co 3 O 4 /ZnO dodecahedral heterojunction as a separator blocking layer which was derived form ZIF-67/ZIF-8 bimetallic MOF. Since the bimetallic oxide heterojunction contains more abundant oxygen vacancies, it has better adsorption and catalytic performances than monometallic oxides. Co 3 O 4 /ZnO coated on the PE separator can effectively block the lithium polysulfides (LiPSs) shuttle due to its good adsorption ability, furthermore, the catalytic effect will accelerate the reaction of LiPSs and improve the electrochemical performances. Consequently, the initial discharge specific capacity of the Co 3 O 4 /ZnO modified separator battery at 0.5 C rate reaches up to 875.5 mAh g−1 when the cathode sulfur areal density is 3 mg cm−2, and still keep 500.9 mAh g−1 after 400 long cycles. Even when the cathode sulfur areal density is 5 mg cm−2, it still shows good cycle stability. • Co 3 O 4 /ZnO dodecahedral heterojunction is derived from ZIF-67/ZIF-8 bimetallic MOF. • Co 3 O 4 /ZnO heterojunction is used as a separator coating material for Li-S battery. • Co 3 O 4 /ZnO heterojunction show excellent absorption and catalytic effect for polysulfides. [ABSTRACT FROM AUTHOR]

• Sn-MOF derived a novel layer structure SnO 2. • Sn-MOF/CNTs derived a novel wool ball-like structure SnO 2 /CNTs composite. • SnO 2 and SnO 2 /CNTs are used as separator coatings for lithium-sulfur batteries. • SnO 2 and SnO 2 /CNTs show good adsorption and catalytic effect on polysulfides. Lithium-sulfur batteries (LSBs) are novel energy storage devices based on their high energy density. However, the application of LSBs faces many difficulties because of several obstacles, especially the shuttle effect of lithium polysulfides (LPs). In order to reduce the influence of the shuttle effect, we conducted the preparation of Sn-MOF which was successfully derived to SnO 2 and SnO 2 /CNTs and applied them as the separator coating layer. SnO 2 can effectively catalyze and adsorb polysulfides based on its unique lamellar structure, and the combination of CNT and SnO 2 further enhances the electrical conductance of the material which accelerates the Li ion migration, and thus improves the electrochemical performances. Experiments showed that the SnO 2 /CNTs coated separator LSB has a discharge capacity of 886.4 mAhg−1 in the first cycle under the sulfur areal density of 2.8 mgcm−2, and after 500 cycles, it still remains 509.6 mAhg−1. Furthermore, under the high sulfur areal density of 5 mgcm−2, the SnO 2 /CNTs modified separator battery still show stable cycle performance which demonstrate its application potential. [ABSTRACT FROM AUTHOR]