Rational Synthesis of Branched CoMoO₄@CoNiO₂ Core/Shell Nanowire Arrays for All-Solid-State Supercapacitors with Improved Performance

Abstract

Effectively composite materials with optimized structures exhibited promising potential in continuing improving the electrochemical performances of supercapacitors in the past few years. Here, we proposed a rational design of branched CoMoO4@CoNiO2 core/shell nanowire arrays on Ni foam by two steps of hydrothermal processing. Owing to the high activity of the scaffold-like CoMoO4 nanowires and the well-defined CoNiO2 nanoneedles, the three-dimensional (3D) electrode architectures achieved remarkable electrochemical performances with high areal specific capacitance (5.31 F/cm(2) at 5 mA/cm(2)) and superior cycling stability(159% of the original specific capacitance, i.e., 95.7% of the maximum retained after 5000 cycles at 30 mA/cm(2)). The all-solid-state asymmetric supercapacitors composed of such electrode and activated carbon (AC) exhibited an areal specific capacitance of 1.54 F/cm(2) at 10 mA/cm(2) and a rate capability (59.75 Wh/kg at a 1464 W/kg) comparable with Li-ion batteries. It also showed an excellent cycling stability with no capacitance attenuation after 50000 cycles at 100 mA/cm(2). After rapid charging (1 s), such supercapacitors in series could lighten a red LED for a long time and drive a mini motor effectively, demonstrating advances in energy storage, scalable integrated applications, and promising commercial potential.

Synthesis of porous flower‐like Ni‐Co‐Mo‐S nanostructures on Ni foam for battery‐supercapacitor hybrid devices

“…After that, a uniformly mixed black slurry was obtained by ultrasonic. Finally, it was dropped into the Ni foam and vacuum‐dried . To calculate the mass load of AC electrode, CV and GCD curves were tested and presented in Figure S11(a),(b), respectively.…”

“…Finally, it was dropped into the Ni foam and vacuum-dried. 56,57 To calculate the mass load of AC electrode, CV and GCD curves were tested and presented in Figure S11(a),(b), respectively. The CV curve showed an approximate rectangular shape, and the GCD curve displayed a linear shape, which were illustrated that the AC electrode exhibited the typical characteristics of an electric double-layer capacitor.…”

Rational Assembly of CoAl‐Layered Double Hydroxide on Reduced Graphene Oxide with Enhanced Electrochemical Performance for Energy Storage

“…In addition, in the first 1000 cycles, there is a heave rolling in specific capacitance, which may be due to the slow activation process. The electrolyte gradually enters into the inner area of electrode corresponding to the activation process of electrode material, which leads to the increase of electrode capacitance . The inset of Figure f exhibits the charge‐discharge curves for the first five and the last five cycles.…”

Carbon Cloth Modified with Metal‐Organic Framework Derived CC@CoMoO4‐Co(OH)2 Nanosheets Array as a Flexible Energy‐Storage Material

“…Figure 7h displays a Ragone plot of the assemble ASC device, which attains up to 61 Wh kg À 1 at a power density of 800 W kg À 1 . Additionally, the ASC device holds about 68 % of the energy density (41.5 Wh kg À 1 ) retention at a higher power density of 16057 W kg À 1 , which is much higher than that of the recently reported ASC devices, such as CC@NiCo 2 O 4 //CC@NC (31.9 Wh kg À 1 at 2900 W kg À 1 ), [20] ZIF-67-LDH-CNP-110//AC (33.29 Wh kg À 1 at 150 W kg À 1 ), [35] CC@Co 3 O 4 // CC@NC (41.5 Wh kg À 1 at 6200 W kg À 1 ), [44] NiCo 2 S 4 @Co(OH) 2 //AC (35.89 Wh kg À 1 at 400 W kg À 1 ), [45] Co 9 S 8 @Ni(OH) 2 //AC (31.35 Wh kg À 1 at 252.8 W kg À 1 ), [46] CoMoO 4 @CoNiO 2 //AC (11.33 Wh kg À 1 at 14.88 kW kg À 1 ) [47] NiCo 2 S 4 @NiO NWAs//AC (30.38 Wh kg À 1 at 288 kW kg À 1 ) . [48] Furthermore, the as-fabricated CC@CoMoO 4 -Co(OH) 2 //AC ASC were performed to assess the flexibility and mechanical stability for wearable electronics in Figure 8.…”