3D Porous Honeycomb‐Like CoN‐Ni₃N/N‐C Nanosheets Integrated Electrode for High‐Energy‐Density Flexible Supercapacitor

Abstract

Transition metal nitrides (TMNs) are considered as potential electrode materials for high‐performance energy storage devices. However, the structural instability during the electrochemical reaction process severely hinders their wide application. A general strategy to overcome this obstacle is to fabricate nanocomposite TMNs on the conducting substrate. Herein, the honeycomb‐like CoN‐Ni3N/N‐C nanosheets are in situ grown on a flexible carbon cloth (CC) via a mild solvothermal method with post‐nitrogenizing treatment. As an integrated electrode for the supercapacitor, the optimized CoN‐Ni3N/N‐C/CC achieves remarkable electrochemical performance due to the enhanced intrinsic conductivity and increased concentration of the active sites. In particular, the flexible quasi‐solid‐state asymmetric supercapacitor assembled with CoN‐Ni3N/N‐C/CC cathode and VN/CC anode delivers an excellent energy density of 106 μWh cm−2, maximum power density of 40 mW cm−2, along with an outstanding cycle stability. This study provides a neoteric perspective on construction of high‐performance flexible energy storage devices with novel metallic nitrides.

Interface Engineering on Cellulose‐Based Flexible Electrode Enables High Mass Loading Wearable Supercapacitor with Ultrahigh Capacitance and Energy Density

“…Furthermore, the flexible ASC device yielded an excellent energy density of 1.42 mWh cm −2 at a power density of 1.15 mW cm −2 and retains 1.01 mWh cm −2 at a power density of 22 mW cm −2 (Figure 5g), which are substantially higher than those of other recently reported supercapacitor devices. [19,45,[58][59][60][61][62][63][64][65] Significantly, one flexible ASC device can light up a timer for 1.5 h and 26 red light emitting diodes (1.8-2.2 V) for several minutes, demonstrating the potential practical applications (Figure 5h,i).…”

Magneto‐Electrodeposition of 3D Cross‐Linked NiCo‐LDH for Flexible High‐Performance Supercapacitors

“…[48,71] The single device delivers a maximum energy density of 0.134 mWh cm −2 at the power density of 1.61 mW cm −2 , which is better than many previously reported devices as shown in Figure 7a and Table S5 (Supporting Information). [72][73][74][75][76][77][78] In order to meet the demand for driving microelectronics, devices were connected in series to boost the voltage window. It is clearly seen that the current density of a single device is nearly two times as high as that of two devices in series, but a half of two devices in parallel (Figure 7b).…”

Creating Unidirectional Fast Ion Diffusion Channels in G/NiS2‐MoS2 Heterostructures for High‐Performance Sodium‐Ion Batteries

“…The degree of capacitive contribution can be analyzed by calculating the b-value from the relationship between current (i) and scanning rate (v) in Equation (1). [18,39] = i av b…”

“…In order to quantitatively analyze the capacitive and diffusion contributions, Equation (1) can be further divided into two parts as Equation (2). [18,39] 1 2 0.5…”