Recent Advancement of Nanostructured Carbon for Energy Applications

A General Electrode Design Strategy for Flexible Fiber Micro‐Pseudocapacitors Combining Ultrahigh Energy and Power Delivery

“…The specific areal capacitance of our solid‐state fiber device with PVA/KOH electrolyte at 0.41 mA cm −2 is ≈2–350 times of previously reported solid‐state fiber SCs measured at much lower rates (typically 0.01–0.1 mA cm −2 ) reported so far (see Table S1, Supporting Information) 1, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36. More importantly, both the areal energy and power densities of 18.83 µWh cm −2 and 16.33 mW cm −2 based on the device (75.32 µWh cm −2 and 65.32 mW cm −2 based on one electrode) are substantially higher than those of previous advanced fiber devices using hollow rGO/PEDOT: PSS fiber (6.8 µWh cm −2 , 0.166 mW cm −2 ),30 rGO/MnO 2 /PPy@metal yarn (9.2 µWh cm −2 , 1.5 mW cm −2 ),31 MnO 2 /CNT fiber (8.5 µWh cm −2 ),20 PPy@CNTs@urethane elastic fibers (6.13 µWh cm −2 , 0.133 mW cm −2 ),26 GO/CNT@carboxymethyl cellulose fibers (3.84 µWh cm −2 , 0.19 mW cm −2 ),5 and nanoporous Au wire@MnO 2 //CNT/carbon fibers (5.4 µWh cm −2 , 2.53 mW cm −2 ) 36.…”

“…As for practical applications with microscale fiber devices, the areal performance is becoming an increasingly important evaluation metric, since the active material mass and the device volume are usually negligible 7. However, the major bottleneck for the existing fiber m‐SCs lies in their much lower areal energy density relative to routine planar SCs8 or batteries 2. In this context, considerable efforts were concentrated on exploring proper fiber electrode materials with large capacitance for improving the energy density, while maintaining high power density 1, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17.…”

“…However, the major bottleneck for the existing fiber m‐SCs lies in their much lower areal energy density relative to routine planar SCs8 or batteries 2. In this context, considerable efforts were concentrated on exploring proper fiber electrode materials with large capacitance for improving the energy density, while maintaining high power density 1, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17. Various carbonaceous materials like activated carbon,9, 10 carbon nanotubes (CNTs),11, 12, 13 reduced graphene oxide (rGO),14, 15, 16 and our recently developed rGO/CNT hybrids17, 18 were exploited as active materials for fiber m‐SCs, yet their applications are restricted by the low capacitance of <200 mF cm −2 .…”

“…To our knowledge, the areal energy and power densities for our prototype device represent the highest values among all solid‐state symmetric fiber SCs (Table S1, Supporting Information). 1, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36 …”

Bio-Sensing Applications of Graphene Based Composite Films

“…It has unique mechanical, electronic, chemical, optical, and thermal properties [1][2][3][4][5]. Particularly its one atom thickness, high charge mobility and high surface-to-volume ratio make it eligible for very sensitive sensing applications [6][7].…”