Electrochemical capacitors: A hierarchical porous graphitic carbon material, composed of macroporous ion-buffering microreservoirs, ion-transporting channels, and localized wall structures, is presented (see images; top: 3D skeleton, bottom: platelet). The properties this new material combine to overcome the electrode kinetic problems normally found in electrochemical capacitors, thus resulting an excellent high-rate energy-storage performance. Supporting information for article available on...

A well-organized flexible interleaved composite of graphene nanosheets (GNSs) decorated with Fe3O4 particles was synthesized through in situ reduction iron hydroxide between GNSs. The GNS/Fe3O4 shows a reversible specific capacity approaching 1026 mA h g−1 after 30 cycles at 35 and 580 mAh 100 700 g−1as well as improved cyclic stability excellent rate capability. multifunctional features the are considered follows: (i) GNSs play "flexible confinement" function to enwrap particles, which can...

In order to achieve high energy and power densities, we developed a high-voltage asymmetric electrochemical capacitor (EC) based on graphene as negative electrode MnO2 nanowire/graphene composite (MGC) positive in neutral aqueous Na2SO4 solution electrolyte. MGC was prepared by solution-phase assembly of sheets α-MnO2 nanowires. Such electrolyte-based ECs can be cycled reversibly the region 0−2.0 V exhibit superior density 30.4 Wh kg−1, which is much higher than those symmetric...

Freestanding and flexible graphene/polyaniline composite paper was prepared by an in situ anodic electropolymerization of polyaniline film on graphene paper. This graphene-based electrode, consisting sheets as building blocks, shows a favorable tensile strength 12.6 MPa stable large electrochemical capacitance (233 F g−1 135 cm−3 for gravimetric volumetric capacitances), which outperforms many other currently available carbon-based electrodes is hence particularly promising supercapacitors.

Hydrous ruthenium oxide (RuO2)/graphene sheet composites (ROGSCs) with different loadings of Ru are prepared by combining sol–gel and low-temperature annealing processes. The graphene sheets (GSs) well-separated fine RuO2 particles (5–20 nm) and, simultaneously, the anchored richly oxygen-containing functional groups reduced, chemically exfoliated GSs onto their surface. Benefits from combined advantages in such a unique structure that ROGSC-based supercapacitors exhibit high specific...

Graphene has been widely used to dramatically improve the capacity, rate capability, and cycling performance of nearly any electrode material for batteries. However, binding between graphene these materials not clearly elucidated. Here we report oxygen bridges with functional groups NiO from analysis by X-ray photoelectron spectroscopy, Fourier transform infrared Raman spectroscopy confirm conformation first-principles calculations. We found that nanosheets (NiO NSs) are bonded strongly...

A unique sandwich structure is designed with pure sulfur between two graphene membranes, which are continuously produced over a large area, as very simple but effective approach for the fabrication of Li–S batteries ultrafast charge/discharge rates and long lifetimes.

Heterogeneous nanocarbon materials are being increasingly investigated and deployed in numerous new technologies devices for sustainable energy conversion storage. Nanocarbons often consist of fullerene, graphene carbon nanotubes. Their derivatives include quantum dots, nanofibres, nanoribbons, nanospheres/capsules other nanostructured morphologies. The heterogeneous forms these nanocarbons stem from the implantation alien atoms into aromatic lattice or covalent grafting functional groups...

Abstract A simple and scalable method to fabricate graphene‐cellulose paper (GCP) membranes is reported; these exhibit great advantages as freestanding binder‐free electrodes for flexible supercapacitors. The GCP electrode consists of a unique three‐dimensional interwoven structure graphene nanosheets cellulose fibers has excellent mechanical flexibility, good specific capacitance power performance, cyclic stability. electrical conductivity the membrane shows high stability with decrease...

Single-crystal ZnO nanowires are synthesized using a vapor trapping chemical deposition method and configured as field-effect transistors. Electrical transport studies show n-type semiconducting behavior with carrier concentration of ∼107cm−1 an electron mobility ∼17cm2∕Vs. The contact Schottky barrier between the Au/Ni electrode nanowire is determined from temperature dependence conductance. Thermionic emission found to dominate mechanism. effect oxygen adsorption on through investigated....

We review the development of carbon–sulfur composites and application for Li–S batteries. Discussions are devoted to synthesis approach various composites, structural transformation sulfur, interaction impacts on electrochemical performances. Perspectives summarized regarding chemistry, electrochemistry industrial production with particular emphasis optimization composites.

Graphene-sulfur (G-S) hybrid materials with sulfur nanocrystals anchored on interconnected fibrous graphene are obtained by a facile one-pot strategy using sulfur/carbon disulfide/alcohol mixed solution. The reduction of oxide and the formation/binding were integrated. G-S hybrids exhibit highly porous network structure constructed graphene, many electrically conducting pathways, easily tunable content, which can be cut pressed into pellets to directly used as lithium-sulfur battery cathodes...

Opening up a band gap and finding suitable substrate material are two big challenges for building graphene-based nanodevices. Using state-of-the-art hybrid density functional theory incorporating long-range dispersion corrections, we investigate the interface between optically active graphitic carbon nitride (g-C3N4) electronically graphene. We find an inhomogeneous planar promotes electron-rich hole-rich regions, i.e., forming well-defined electron–hole puddle, on supported graphene layer....

A flexible Li–S battery based on an integrated structure of sulfur and graphene a separator is developed. The internal current collector offers continuous conductive pathway, modified interface with sulfur, good barrier to effective reservoir for dissolved polysulfides, consequently improving the capacity cyclic life battery. As service our authors readers, this journal provides supporting information supplied by authors. Such materials are peer reviewed may be re-organized online delivery,...

Mesoporous carbon with homogeneous boron dopant was prepared by co-impregnation and carbonization of sucrose boric acid confined in mesopores SBA-15 silica template. Low-level doping shows catalytic effect on oxygen chemisorption at edge planes alters electronic structure space charge layer doped mesoporous carbon. These characteristics are responsible for substantial improvement interfacial capacitance 1.5−1.6 times higher boron-doped than that boron-free alkaline electrolyte (6 M KOH)...

We report the template-directed synthesis of sulphur–carbon nanotubes and their use to form a membrane that is binder-free, highly conductive flexible. This nanostructured used as self-supporting cathode without metal current-collectors for Li-S batteries. The has high electrical conductivity renders long life sulphur over 100 charge–discharge cycles. High discharge capacity was attained at 712 mA h gsulphur−1 (23 wt% S) 520 (50 current density (6 A gsulphur−1). overall flexible...

Elektrochemische Kondensatoren: Ein hierarchisches poröses Material auf Graphitbasis enthält makroporöse ionengepufferte Mikroreservoirs, Kanäle für den Ionentransport und lokalisierte Graphitstrukturen (siehe Bilder des Gerüsts (oben) eines Kohlenstoffplättchens). Das neue löst Probleme der Elektrodenkinetik, die anderen elektrochemischen Kondensatoren anhaften, ist daher hervorragend schnelle Energiespeicherung geeignet.

Ether solvent is utilized to manipulate the SEI on high specific surface area carbon enable achievement of superb sodium storage performance.

Abstract Ether based electrolytes have surfaced as alternatives to conventional carbonates allowing for enhanced electrochemical performance of sodium-ion batteries; however, the primary source improvement remains poorly understood. Here we show that coupling titanium dioxide and other anode materials with diglyme does enable higher efficiency reversible capacity than those combination involving ester electrolytes. Importantly, electrolyte dependent is revealed be result different structural...

A nitrogen-doped porous carbon monolith was synthesized as a pseudo-capacitive electrode for use in alkaline supercapacitors. Ammonia-assisted carbonization used to dope the surface with nitrogen heteroatoms way that replaced atoms but kept oxygen content constant. Ammonia treatment expanded micropore size-distributions and increased specific area from 383 m(2) g(-1) 679 g(-1). The nitrogen-containing material showed higher capacitance (246 F g(-1)) comparison nitrogen-free one (186 g(-1))....