Аннотации:
Rechargeable lithium/sulfur (Li/S) batteries have received quite significant attention over
the years because of their high theoretical specific capacity (1672 mAh g1) and energy density
(2600 mAh g1) which has led to more efforts for improvement in their electrochemical performance.
Herein, the synthesis of a flexible freestanding sulfur/polyacrylonitrile/graphene oxide (S/PAN/GO)
as the cathode for Li/S batteries by simple method via vacuum filtration is reported. The S/PAN/GO
hybrid binder-free electrode is considered as one of the most promising cathodes for Li/S batteries.
Graphene oxide (GO) slice structure provides effective ion conductivity channels and increases
structural stability of the ternary system, resulting in excellent electrochemical properties of the
freestanding S/PAN/GO cathode. Additionally, graphene oxide (GO) membrane was able to
minimize the polysulfides’ dissolution and their shuttle, which was attributed to the electrostatic
interactions between the negatively-charged species and the oxygen functional groups on GO.
Furthermore, these oxygen-containing functional groups including carboxyl, epoxide and hydroxyl
groups provide active sites for coordination with inorganic materials (such as sulfur). It exhibits the
initial reversible specific capacity of 1379 mAh g1 at a constant current rate of 0.2 C and maintains
1205 mAh g1 over 100 cycles (~87% retention). In addition, the freestanding S/PAN/GO cathode
displays excellent coulombic efficiency (~100%) and rate capability, delivering up to 685 mAh g1
capacity at 2 C