We have successfully constructed a new type of intercalation membrane material by covalently grafting organic tris(hydroxypropyl)phosphine (THPP) molecules onto hydroxylated multi-walled carbon nanotubes (CNT-OH) as a functional interlayer for the advanced LSBs. The as-assembled interlayer has been demonstrated to be responsible for the fast conversion kinetics of polysulfides, the inhibition of polysulfide shuttle effect, as well as the formation of a stable solid electrolyte interphase(SEI) layer. By means of spectroscopic and electrochemical analysis, we further found THPP plays a key role in accelerating the conversion of polysulfides into low-ordered lithium sulfides and suppressing the loss of polysulfides, thus rendering the asdesigned lithium-sulfur battery in this work a high capacity, excellent rate performance and long-term stability. Even at low temperatures, the capacity decay rate was only 0.036 % per cycle for 1700 cycles.

Rational design of the sulfur cathode structure enables effective adsorption of polysulfides and accelerates the sulfur reduction reaction, which is of great significance to the practical application of lithium–sulfur batteries. Here, P-doped carbon foam (PCF) as a sulfur host for the lithium–sulfur battery cathode was successfully synthesized by a facile strategy. The tailored hierarchical pore structure combined with P doping not only facilitates Li+ diffusion but also enhances the adsorption and accelerates the catalytic conversion of lithium polysulfides, thus significantly improving lithium storage performance of the PCF/S cathode.

In this study, cuboid‐like anhydrous CoC2O4 particles (CoC2O4‐HK) are synthesized through a potassium citrate‐assisted hydrothermal method, which possess well‐crystallized structure for fast Li+ transportation and efficient Li+ intercalation pseudocapacitive behaviors. When being used in lithium‐ion batteries, the as‐prepared CoC2O4‐HK delivers a high reversible capacity (≈1360 mAh g‐1 at 0.1 A g‐1), good rate capability (≈650 mAh g‐1 at 5 A g‐1) and outstanding cycling stability (835 mAh g‐1 after 1000 cycles at 1 A g‐1). Characterizations illustrate that the Li+‐intercalation pseudocapacitance dominates the charge storage of CoC2O4‐HK electrode, together with the reversible reaction of CoC2O4+2Li++2e−→Co+Li2C2O4 on discharging and charging. In addition, CoC2O4‐HK particles are also used together with carbon–sulfur composite materials as the electrocatalysts for lithium–sulfur (Li–S) battery, which displays a gratifying sulfur electrochemistry with a high reversibility of 1021.5 mAh g−1 at 2 C and a low decay rate of 0.079% per cycle after 500 cycles. The density functional theory (DFT) calculations show that CoC2O4/C can regulate the adsorption‐activation of reaction intermediates and therefore boost the catalytic conversion of polysulfides. Therefore, this work presents a new prospect of applying CoC2O4 as the high‐performance electrode materials for rechargeable Li‐ion and Li–S batteries.

Herein, we investigated in detail the effect of metal valences in different cobalt‐based organic framework compounds on the kinetics of sulfur reaction in lithium‐sulfur batteries (LSBs). On this basis, two organic framework compounds of zeolite‐imidazole‐based cobalt organic framework compound (Co‐ZIF) and tetrakis(4‐benzoic acid) porphyrinato‐CoIII chloride [Co‐TBP(III)] with different valences were constructed as the functional intercalation separators of LSBs, and explored the effects of different valences on improving the reaction kinetics of polysulfides and inhibiting the shuttle effect. Experiments and theoretical calculations prove that CoII exhibits the best catalytic activity. This is mainly due to the fact that +2 valence shows a strong adsorption energy for polysulfides and a higher Fermi level compared with +3 valence, thus improving the efficiency of the rapid catalytic conversion of sulfur species. As expected, the discharge specific capacity of Co‐ZIF as the catalytic layer of the LSBs reached 772.7 mAh g−1 at a high current density of 5 C. More importantly, the initial specific capacity is 839.6 mAh g−1 at high current 3 C, and after 720 cycles, the attenuation rate of per cycle is only 0.092 %, and the coulombic efficiency remains above 92 %.

We have successfully constructed a new type of intercalation membrane material by covalently grafting organic tris(hydroxypropyl)phosphine (THPP) molecules onto hydroxylated multi-walled carbon nanotubes (CNT-OH) as a functional interlayer for the advanced LSBs. The as-assembled interlayer has been demonstrated to be responsible for the fast conversion kinetics of polysulfides, the inhibition of polysulfide shuttle effect, as well as the formation of a stable solid electrolyte interphase(SEI) layer. By means of spectroscopic and electrochemical analysis, we further found THPP plays a key role in accelerating the conversion of polysulfides into low-ordered lithium sulfides and suppressing the loss of polysulfides, thus rendering the asdesigned lithium-sulfur battery in this work a high capacity, excellent rate performance and long-term stability. Even at low temperatures, the capacity decay rate was only 0.036 % per cycle for 1700 cycles.