Superhighway channels of nickel ferrite doped Polyaniline nanocomposites
for a high-performance stable symmetric pseudo-supercapacitor
Abstract
The electrochemical performance of Polyaniline (PANI) can be
significantly improved due to the incorporation of spinel-type
transition metal oxide, i.e., 1 wt. % of Nickel Ferrite (NiFe
2O 4) into the PANI matrix. In this
report, we have synthesised NiFe 2O 4
(NF), PANI1:1 ratio, PANI1:2 ratio, and PANI/NiFe 2O
4 nanocomposites, i.e., PANI1:1/NF1 and PANI1:2/NF2
nanocomposites by in-situ oxidative polymerization method. The
conducting network formed in the nanocomposite significantly increases
the multiple valence states of the metal for the electrolytic ions. The
PANI/NiFe 2O 4 nanocomposite shows good
interaction and was confirmed by Fourier Transform Infra-red
Spectroscopy (FTIR) and Raman analysis. The SEM analysis reveals a
uniformly porous and agglomerated globular morphology of the
nanocomposite. Also, the PANI/NiFe 2O 4
composite (PANI1:1/NF1) exhibits enhanced supercapacitive properties due
to improve strong conducting path of PANI, which helps to provide the
delocalization of the electrons in the polymeric chain. The highest
specific capacitance ~ 758 Fg -1 is
achieved for PANI 1:1/NF1 sample as compared to bare PANI1:1 (677 Fg
-1), PANI1:2 (500 Fg -1), NF (253 Fg
-1) and other PANI1:2/NF2 (686 Fg
-1) samples at 10 mV/s scan rate in a two-electrode
system due to NF nanoparticles filling the vacant places in the
polymeric matrix. The energy density (54 Whkg -1),
power density (1705 Wkg -1) and good cycling stability
approx. 97 % after 10000 GCD cycles of the device is found for
PANI1:1/NF1. The EIS studies further confirm that the PANI 1:1/NF1
device has a lower charge transfer resistance (R ct)
~ 0.35 Ohm in comparison to other fabricated devices. It
seems that NiFe 2O 4 acts as a
“superhighway” for charge transportation between PANI which is
beneficial for supercapacitors.