Nature Research, Scientific Reports, 1(7), 2017
DOI: 10.1038/s41598-017-18108-0
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AbstractWe design the Janus-like interlayer with two different functional faces for suppressing the shuttle of soluble lithium polysulfides (LPSs) in lithium-sulfur batteries (LSBs). At the front face, the conductive functionalized carbon fiber paper (f-CFP) having oxygen-containing groups i.e., -OH and -COOH on its surface was placed face to face with the sulfur cathode serving as the first barrier accommodating the volume expansion during cycling process and the oxygen-containing groups can also adsorb the soluble LPSs via lithium bonds. At the back face, a crystalline coordination network of [Zn(H2PO4)2(TzH)2]n (ZnPTz) was coated on the back side of f-CFP serving as the second barrier retarding the left LPSs passing through the front face via both physical confinement and chemical adsorption (i.e. Li bonding). The LSB using the Janus-like interlayer exhibits a high reversible discharge capacity of 1,416 mAh g−1 at 0.1C with a low capacity fading of 0.05% per cycle, 92% capacity retention after 200 cycles and ca. 100% coulombic efficiency. The fully charged LSB cell can practically supply electricity to a spinning motor with a nominal voltage of 3.0 V for 28 min demonstrating many potential applications.