Bridged Carbon Fabric Membrane with Boosted Performance in AC Line‐Filtering Capacitors

Abstract

High-frequency responsive capacitors with lightweight, flexibility, and miniaturization are among the most vital circuit components because they can be readily incorporated into various portable devices to smooth out the ripples for circuits. Electrode materials no doubt are at the heart of such devices. Despite tremendous efforts and recent advances, the development of flexible and scalable high-frequency responsive capacitor electrodes with superior performance remains a great challenge. Herein, a straightforward and technologically relevant method is reported to manufacture a carbon fabric membrane "glued" by nitrogen-doped nanoporous carbons produced through a polyelectrolyte complexation-induced phase separation strategy. The as-obtained flexible carbon fabric bearing a unique hierarchical porous structure, and high conductivity as well as robust mechanical properties, serves as the free-standing electrode materials of electrochemical capacitors. It delivers an ultrahigh specific areal capacitance of 2632 μF cm −2 at 120 Hz with an excellent alternating current line filtering performance, fairly higher than the state-of-the-art commercial ones. Together, this system offers the potential electrode material to be scaled up for AC line-filtering capacitors at industrial levels.

Hierarchical Multiscale Engineered Fe3O4/Ni Electrodes with Ultrafast Supercapacitive Energy Storage for Alternate Current Line‐Filtering

“…Epitaxy of the deposited layers was investigated by X-ray diffraction (XRD) as shown in Figure 3. 2θ/ω measurement on the Au/Ti/c-Al 2 O 3 substrate (bottom of Figure 3a) shows the Au layer is epitaxial along an [111] out-of-plane orientation; the Ti (0002) reflection is very weak. Despite the relatively large lattice match (-14%) between Ni (111) and Au (111), only Ni (111) and Ni (222) reflections are observed for both dense Ni (D-Ni) (middle of Figure 3a) and 3D mesostructured Ni (M-Ni) (top of Figure 3a).…”

“…2θ/ω measurement on the Au/Ti/c-Al 2 O 3 substrate (bottom of Figure 3a) shows the Au layer is epitaxial along an [111] out-of-plane orientation; the Ti (0002) reflection is very weak. Despite the relatively large lattice match (-14%) between Ni (111) and Au (111), only Ni (111) and Ni (222) reflections are observed for both dense Ni (D-Ni) (middle of Figure 3a) and 3D mesostructured Ni (M-Ni) (top of Figure 3a). The crystallite sizes (D) of nickel were estimated with the Ni (111) peaks using the Scherrer equation, [72,78] yielding 31 nm for D-Ni and 33 nm for M-Ni, respectively.…”

“…The six reflections separated azimuthally (φ) by 60°at Ψ ¼ 30 and 80°indicate two Ni {111} domains that are antiparallel to each other. [80] When deposited on the c-Al 2 O 3 , Au (111) and Ti (0001) layers are also known to consist of two domains 180°rotated to each other. [53,81] Therefore, two types of in-plane epitaxial relationships with respect to the sapphire are present in M-Ni: Ni (111)½110//Au (111)½110// Ti (0002)½1210//Al 2 O 3 (0006)½1100 (parallel) and Ni (111)½110// Au (111)½110//Ti (0002)½1210//Al 2 O 3 (0006)½1100 (antiparallel).…”

“…Figure S2, Supporting Information, supports our interpretation. The epitaxial Fe 3 O 4 (111) film forms on the Ni (111) surface by continuous potentiostatic electrodeposition.…”

“…The Fe 3 O 4 nanosheets are uniformly grown on the Ni surface via pulsed electrodeposition, enabling the formation of M-Fe 3 O 4 /Ni. As will be shown later, the 3D mesostructured Ni is epitaxial along both out-of-plane and in-plane orientations (Δa ¼ À14% for Ni (111)/Au (111)).…”