Three-dimensional P-doped carbon skeleton with built-in Ni2P nanospheres as efficient polysulfides barrier for high-performance lithium-sulfur batteries

摘要

Rational design of modified separator is of great significance in effectively suppressing the shuttle of lithium polysulfides (LiPSs) and hence realizing fulfilling cycling performance of lithium-sulfur batteries (LSBs). In this paper, we developed a facile strategy to fabricate P-doped carbon coated CNT skeleton coupled with nickel phosphide (Ni2P) nanospheres (PCCNT@NPS), and then we employed the as developed hybrid as a multifunctional modified interlayer onto PP separator (denoted as PCNPmPP) to face the challenge of LiPSs shuttling. The as-prepared hybrid provides abundant physical confinement and strong chemical adsorption for inhibiting polysulfides shuttling as well as efficient catalysis for accelerating LiPSs converting. As a result, the LSBs based on PCCNT@NPS modified PP separator have delivered a highly reversible cycling performance with high initial discharge capacity of 1067 mAh g(-1) and low capacity decay rate of 0.077% per cycle within 500 cycles at 1 C. The promising results demonstrate that the PCCNT@NPS composite is capable of effectively inhibiting the diffusion and shuttle of LiPSs. This paper provides a novel thinking for the synthesis of multifunctional interlayer onto PP separator for advanced LSBs. (C) 2019 Elsevier Ltd. All rights reserved.