Electric double layer capacitors for ac filtering made from vertically oriented graphene nanosheets on aluminum

Ultrahigh‐Rate Supercapacitor Based on Carbon Nano‐Onion/Graphene Hybrid Structure toward Compact Alternating Current Filter

“…From these comparisons and Table S2 (Supporting Information), it can be seen that the hybrid structure has a higher AC filtering electrochemical performance than that of single component, which can be ascribed to the synergistic effect of CNOs and graphene. The C A of 145 µF cm −2 obtained in our study is higher than those of capacitor devices operated at 120 Hz based on different materials, including commercial AECs (630 pF cm −2 , measured in our study shown in Figure S11, Supporting Information), VOGNs (<100 µF cm −2 ), [ 1,25,26,29 ] PEDOT:PSS/exfoliated graphene (28 µF cm −2 ), [ 16 ] and CNT film (106 µF cm −2 ), [ 31 ] B/N‐doped CNTs, [ 68 ] and comparable to those based on meso/macroporous carbon sponge (172 µF cm −2 ), [ 35 ] PEDOT film (150 µF cm −2 ), [ 17 ] and TTF‐TCNO/graphene hybrid structure (151 µF cm −2 ). [ 69 ] Moreover, a high volumetric specific capacitance ( C v ) at 120 Hz of 4.9 F cm −3 was achieved in EDLC (I/II/A) due to the very thin average thickness of the CNO‐graphene hybrid‐structured film (≈150 nm measured by AFM and cross‐sectional SEM image shown in Figure S13, Supporting Information), indicating a potential application in compact AC‐line filtering and energy storage.…”

“…[1,9,13,16] With regard to the efforts in carbon nanostructures, vertically oriented graphene and carbon nanotube (CNT) structures have shown excellent AC filtering capacitive behavior owing to their high conductivity, relatively large pores, and straightforward transportation path. [1,3,[25][26][27][28][29] However, the vertical graphitic nanostructures have higher height than the film structure, resulting in lower E v and lower rate capability. Also, the synthesis of vertical graphitic structures usually requires harsh and complicated manufacturing process, such as plasma-enhanced chemical vapor deposition (CVD) or hot-filament assisted reducing CVD, which limits the scalable and cost-effective synthesis of electrode materials.…”

Platinum Nanoparticle in Tantalum Electrode for the Electrochemical Analysis of Heavy Metal Ions Formed by the Ion Beam Sputtering Deposition

“…Therefore, it is urgently necessary to build metal ion sensors with a broader range of detections and high sensitivity. Graphene is a single-atomic layer of tightly packed carbon atoms in a two-dimensional wave [8,9]. Due to its high electronic mobility, wide surface area and the prevalence of exposed edge planes for greatly raising the storage of charges, platinum has tremendous potential to be used in the production of chemo sensors [10].…”

All Fiber Based Electrochemical Capacitor towards Wearable AC Line Filters with Outstanding Rate Capability

“…[7] Electrochemical capacitors (supercapacitors or SCs) are under consideration to replace AECs due to the advantages of high specific capacitance, lightweight and small size. [17] This deposited vertically graphene sheet has an ordered structure that has been widely applied due to the easy access to the fast ion transportation and good rate capability. It is attributed to activated carbon with a complex porous structure, which is not conducive to the movement of electrolyte ions.…”

“…[11][12][13][14][15][16] Butler et al deposited vertically oriented graphene sheets on aluminum foil by chemical vapor deposition (CVD) and then obtained SCs efficiently filtering a 120 Hz ripple. [17] This deposited vertically graphene sheet has an ordered structure that has been widely applied due to the easy access to the fast ion transportation and good rate capability. However, the SCs by CVD method are still far from scalable manufacture and the as-fabricated devices cannot meet the needs of wearable devices.…”