Version 2 2023-12-07, 23:03Version 2 2023-12-07, 23:03
Version 1 2023-12-05, 21:04Version 1 2023-12-05, 21:04
journal contribution
posted on 2023-12-07, 23:03authored byHakan Bildirir, Diego Alván, Nagaraj Patil, Victor A. de la Peña O’Shea, Marta Liras, Rebeca Marcilla
Organic macromolecules bearing redox-active units are
projected
to be promising candidates as safe and sustainable alternatives to
current inorganic intercalation electrodes in Li-ion batteries (LIBs).
Although a range of redox polymers with various sizes, architectures,
and topologies have been successfully evaluated in LIBs, cost-effective
polymerization routes toward their synthesis are rarely considered.
Here, a cost-effective synthetic route was employed to synthesize
a hypercrosslinked polymeric network bearing a representative p-type
organic redox functionality known as phenothiazine. This hypercrosslinked
phenothiazine polymer (named IEP-29) was subsequently evaluated as
an organic cathode in a lithium battery. The hereby used “knitting”
polymerization technique operating through the Friedel–Crafts
mechanism allowed us to produce the final atom-economic polymeric
network. The material features a remarkably high density of phenothiazine
redox units connected by only allylic carbons (−CH2−), unlike bulky crosslinkers used for the production of common
hyperbranched/porous polymers. The IEP-29 cathode delivered high capacity
(106 mAh g–1 at 0.5C), close to the theoretical
value, high potential output (3.6 V vs Li/Li+), excellent
rate capability (60 mAh g–1 at 15C), and good cycle
stability (79% capacity retention after 1000 cycles at 2C). Since
the hereby used “knitting” method is a quite facile
method to polymerize low-cost materials in high yields, the findings
pave the way for valorization of the organic electrode materials for
scalable applications without compromising the performance.