1 research outputs found
High-Performance Flexible Solid-State Supercapacitor with an Extended Nanoregime Interface through in Situ Polymer Electrolyte Generation
Here, we report an efficient strategy
by which a significantly enhanced electrode–electrolyte interface
in an electrode for supercapacitor application could be accomplished
by allowing in situ polymer gel electrolyte generation inside the
nanopores of the electrodes. This unique and highly efficient strategy
could be conceived by judiciously maintaining ultraviolet-triggered
polymerization of a monomer mixture in the presence of a high-surface-area
porous carbon. The method is very simple and scalable, and a prototype,
flexible solid-state supercapacitor could even be demonstrated in
an encapsulation-free condition by using the commercial-grade electrodes
(thickness = 150 μm, area = 12 cm<sup>2</sup>, and mass loading
= 7.3 mg/cm<sup>2</sup>). This prototype device shows a capacitance
of 130 F/g at a substantially reduced internal resistance of 0.5 Ω
and a high capacitance retention of 84% after 32000 cycles. The present
system is found to be clearly outperforming a similar system derived
by using the conventional polymer electrolyte (PVA–H<sub>3</sub>PO<sub>4</sub> as the electrolyte), which could display a capacitance
of only 95 F/g, and this value falls to nearly 50% in just 5000 cycles.
The superior performance in the present case is credited primarily
to the excellent interface formation of the in situ generated polymer
electrolyte inside the nanopores of the electrode. Further, the interpenetrated
nature of the polymer also helps the device to show a low electron
spin resonance and power rate and, most importantly, excellent shelf-life
in the unsealed flexible conditions. Because the nature of the electrode–electrolyte
interface is the major performance-determining factor in the case
of many electrochemical energy storage/conversion systems, along with
the supercapacitors, the developed process can also find applications
in preparing electrodes for the devices such as lithium-ion batteries,
metal–air batteries, polymer electrolyte membrane fuel cells,
etc