Akademik Veri Yönetim Sistemi
Journal of Materials Science: Materials in Electronics , cilt.35, sa.1681, ss.1-25, 2024 (SCI-Expanded)
Polypyrrole/electrolytic manganese dioxide (PPy/EMD) composite is
fabricated electrochemically on a stainless-steel mesh (SSM) surface in
acetonitrile containing EMD nanorods and pyrrole monomer as a
supercapacitor anode electrode material. EMD is recovered with an
efficiency of 96.2% from a methanesulfonic acid leached solution of
spent Li-ion batteries using an iridium-tantalum-coated titanium anode.
The composite-coated electrode is characterized using electrochemical
impedance spectroscopy (EIS) and cyclic voltammetry (CV) by comparison
with those of its components: the electrode with a mass loading of 10
mg.cm-2 has the highest specific capacitance (72 F g-1) and pseudocapacitive contribution (95% at 50 mV s-1) and the lowest resistance (1.85 Ω cm2).
Spectroscopic studies of the composite coating are carried out using
energy-dispersive X-ray spectroscopy (EDX) and X-ray photoelectron
spectroscopy (XPS), while the morphological and structural analyses are
performed using field emission scanning electron microscopy (FESEM),
transmission electron microscopy (TEM), and X-ray diffraction (XRD). EMD
nanoparticles with ε-MnO2 and oxygen-deficient structure are
homogeneously distributed in the composite at 8.4 wt% and encapsulated
within the growing PPy clusters. Thus, due to the pseudocapacitive
behavior, EMD recovered from batteries contributes significantly to the
capacitance of the composite. PPy/EMD- and C- coated electrodes are
combined in polyvinyl alcohol/Li2SO4 gel electrolyte to construct an asymmetric supercapacitor cell: it has a 23.2 Wh.kg-1 energy density and a 0.31 kW.kg-1 power density at 0.50 A.g-1
from the galvanostatic charge-discharge (GCD) test. After 5000 cycles,
cycle life is 74.0% with a coulombic efficiency of 77.7%.