Hybrid NiO–CuO mesoporous nanowire array with abundant oxygen vacancies and a hollow structure as a high-performance asymmetric supercapacitor

Abstract

This work presents an asymmetric supercapacitor based on advanced 3D hollow architectures of NiO–CuO mesoporous nanowires with high areal/specific capacitances and cycling stability.

Fabrication of novel hybrid composite La2-xCoxCuO4electrode for high performance supercapacitors

“…XRD pattern of hybrid composite with 0.1%, 0.2%, and 0.3% content of cobalt in La 2 CuO 4 is shown in Figure B‐D, which represents diffraction peaks at 41.27, 41.86, 42.57, 43.50, 52.84, 54.59, 55.97, 56.89, 58.11, and 58.41 degree and is indexed to hybrid composite La 2 (Co 0.75 Cu 0.25 )O 4.1 phase with tetragonal structure and Bmab/Abma space group (82‐1663 and 82‐1941). The other diffraction peaks at 43.55, 43.60, 44.58, 47.43, 47.91, and 52.03 are indexed to La 2 O 3 and La 2 CuO 4 phases . It is obvious that there was mixed phases in Figure B,C; however, the pure phase solid solution was obtained with 0.3% cobalt content in the base material as shown in Figure D.…”

“…Figure 1A, for pure La 2 CuO 4 , exhibits diffraction peaks at 42.84, 44.58, 48.84, and 55.40 degree, which can be indexed to orthorhombic structure with Cmmm space group (79-0453). XRD Figure 1B 27 It is obvious that there was mixed phases in Figure 1B,C; however, the pure phase solid solution was obtained with 0.3% cobalt content in the base material as shown in Figure 1D. Figure 2A with large sizes.…”

3D Structural Strengthening Urchin‐Like Cu(OH)2‐Based Symmetric Supercapacitors with Adjustable Capacitance

“…The excellent C v should be attributed to well‐designed high‐surface‐area lattice spatial framework, hierarchical functional materials, and developed pathways for high‐speed intercalation/deintercalation of ions. Table 1 compared the capacitance of various electrode materials in recently reported researches . Obviously, the volumetric and gravimetric capacitance of 3D lattice electrodes was competitive in current researches.…”

Hybrid Supercapacitors Based on Interwoven CoO‐NiO‐ZnO Nanowires and Porous Graphene Hydrogel Electrodes with Safe Aqueous Electrolyte for High Supercapacitance

“…Moreover, comparing the XRD pattern of CoO-NiO with that of CoO-NiO-ZnO (CNZO) as shown in Figure 2, it can be seen clearly that a new peak located at 33.7° belongs to (100) crystal plane of hexagonal ZnO (JCPDS no. [49] Compared with these clear lattice fringes, the lattice fringes at the edges (the areas indicated by the green arrows) are blurred significantly, due to the presence of many oxygen vacancy defects on the surface produced by annealing under a nitrogen atmosphere probably. However, according to the literature we cannot exclude the possibility of formation of solid-solution CoO-NiO due to their similar lattice and interplanar distances of NiO and CoO.…”

“…[24,47,48] In the present case, cubic CoO and cubic NiO both have crystal planes such as (111), (200), and (220). [49] Figure S6, Supporting Information, shows the low-resolution TEM image of CNZO, and Figure S7, Supporting Information, shows the corresponding element mapping, the four elements Zn, Co, Ni, and O can be clearly seen. [49] Compared with these clear lattice fringes, the lattice fringes at the edges (the areas indicated by the green arrows) are blurred significantly, due to the presence of many oxygen vacancy defects on the surface produced by annealing under a nitrogen atmosphere probably.…”