posted on 2024-03-16, 15:15authored byBhanu Ranjan, Davinder Kaur
Pseudocapacitive kinetics in rationally
engineered nanostructures
can deliver higher energy and power densities simultaneously. The
present report reveals a high-performance all-solid-state flexible
symmetric supercapacitor (FSSC) based on MoS2–Mo2N nanowires deposited directly on stainless steel mesh (MoS2–Mo2N/SSM) employing DC reactive magnetron
co-sputtering technology. The abundance of synergistically coupled
interfaces and junctions between MoS2 nanosheets and Mo2N nanostructures across the nanocomposite results in greater
porosity, increased ionic conductivity, and superior electrical conductivity.
Consequently, the FSSC device utilizing poly(vinyl alcohol)-sodium
sulfate (PVA-Na2SO4) hydrogel electrolyte renders
an outstanding cell capacitance of 252.09 F·g–1 (44.12 mF·cm–2) at 0.25 mA·cm–2 and high rate performance within a wide 1.3 V window. Dunn’s
and b-value analysis reveals significant energy storage
by surface-controlled capacitive and pseudocapacitive mechanisms.
Remarkably, the symmetric device boosts tremendous energy density
∼10.36 μWh·cm–2 (59.17 Wh·kg–1), superb power density ∼6.5 mW·cm–2 (37.14 kW·kg–1), ultrastable
long cyclability (∼93.7% after 10,000 galvanostatic charge–discharge
cycles), and impressive mechanical flexibility at 60°, 90°,
and 120° bending angles.