Ultrathin NiCo-MOF Nanosheets for High-Performance Supercapacitor Electrodes

Abstract

Metal–organic frameworks (MOFs) have attracted intensive attention for high-performance supercapacitors owing to their large specific surface area and tunable pore structure. Herein, ultrathin NiCo-MOF nanosheets are fabricated by a facile ultrasonication at room temperature and employed as a supercapacitor electrode material. The unique nanosheet-like structure of NiCo-MOF provides more electroactive sites and a shorter pathway for electron transfer and electrolyte diffusion, resulting in excellent electrochemical performance with a high specific capacitance of 1202.1 F g–1 at 1 A g–1. In addition, an asymmetric supercapacitor of NiCo-MOF//activated carbon was assembled in 2 M KOH electrolyte. It delivers an energy density of 49.4 W h kg–1 at a power density of 562.5 W h kg–1 in a voltage window of 1.5 V. The results demonstrate a new method to fabricate ultrathin MOF nanosheets for high-performance supercapacitor electrode materials.

Hydrangea‐like NiCo‐based Bimetal‐organic Frameworks, and their Pros and Cons as Supercapacitor Electrode Materials in Aqueous Electrolytes

“…A group of peaks at 1596, 825, 761, and 679 cm –1 are assigned to the characteristic mode of aromatic ring . The two strong bands at 1541 and 1381 cm –1 are ascribed to the asymmetric and symmetric stretching modes of the coordinated carboxyl group from BPDC . All these confirm that BPDC ligands exist in the as‐synthesized NiCo‐MOF.…”

“…GCD tests were performed from 0 V to 0.4 V at different current densities. The corresponding specific capacitances of active electrodes were calculated from GCD curves according to the equation in literature . EIS measurements were conducted in a frequency range from 100 kHz to 0.01 Hz under open circuit voltage.…”

Incorporating Ni-MOF structure with polypyrrole: enhanced capacitive behavior as electrode material for supercapacitor

“…3D) is also obtained, which can be tted into two peaks corresponding to the oxygen atoms in O]C-O (531.7 eV) groups of the terephthalic acid linker and -OH (532.8 eV). 38 The abovementioned analyses indicate that the PPy-MOF composite are fabricated successfully.…”

“…3C) can be divided into three peaks located at 284.7, 285.6, and 288.2 eV, which can be assigned to C-C, C]O, and O-C] O, respectively. 38,39 In addition, the XPS spectrum of O 1s (Fig. 3D) is also obtained, which can be tted into two peaks corresponding to the oxygen atoms in O]C-O (531.7 eV) groups of the terephthalic acid linker and -OH (532.8 eV).…”

Two‐Dimensional MOF and COF Nanosheets: Synthesis and Applications in Electrochemistry

“…Similarly, Wang and co‐workers applied CoCl 2 ⋅6 H 2 O and NiCl 2 ⋅6 H 2 O into terephthalic acid (PTA) in 1:2 ratio to synthesize ultrathin NiCo‐MOF nanosheets with the thickness of 1.74–3.87 nm. (Figure d).…”