Three-dimensional (3D) N-doped graphene aerogel (N-GA)-supported Fe(3)O(4) nanoparticles (Fe(3)O(4)/N-GAs) as efficient cathode catalysts for the oxygen reduction reaction (ORR) are reported. The hybrids exhibit an interconnected macroporous framework of sheets with uniform dispersion (NPs). In studying effects carbon support on NPs ORR, we found that Fe(3)O(4)/N-GAs show a more positive onset potential, higher cathodic density, lower H(2)O(2) yield, and electron transfer number ORR in...

Mass production of high-quality graphene sheets is essential for their practical application in electronics, optoelectronics, composite materials, and energy-storage devices. Here we report a prompt electrochemical exfoliation into aqueous solutions different inorganic salts ((NH4)2SO4, Na2SO4, K2SO4, etc.). Exfoliation these electrolytes leads to with high yield (>85%, ≤3 layers), large lateral size (up 44 μm), low oxidation degree (a C/O ratio 17.2), remarkable hole mobility 310 cm2 V–1...

Micro-supercapacitors are important on-chip micro-power sources for miniaturized electronic devices. Although the performance of micro-supercapacitors has been significantly advanced by fabricating nanostructured materials, developing thin-film manufacture technologies and device architectures, their power or energy densities remain far from those electrolytic capacitors lithium batteries. Here we demonstrate graphene-based in-plane interdigital on arbitrary substrates. The resulting deliver...

Solution-processable thin layer graphene is an intriguing nanomaterial with tremendous potential for electronic applications. In this work, we demonstrate that electrochemical exfoliation of graphite furnishes sheets high quality. The electrochemically exfoliated (EG) contains a yield (>80%) one- to three-layer flakes C/O ratio 12.3 and low sheet resistance (4.8 kΩ/□ single EG sheet). Due the solution processability EG, vacuum filtration method in association dry transfer introduced produce...

The high cost of platinum-based electrocatalysts for the oxygen reduction reaction (ORR) has hindered practical application fuel cells. Thanks to its unique chemical and structural properties, nitrogen-doped graphene (NG) is among most promising metal-free catalysts replacing platinum. In this work, we have developed a cost-effective synthesis NG by using cyanamide as nitrogen source oxide precursor, which led controllable contents (4.0% 12.0%) after pyrolysis. thermally treated at 900 °C...

Nitrogen-doped carbon nanosheets (NDCN) with size-defined mesopores are reported as highly efficient metal-free catalyst for the oxygen reduction reaction (ORR). A uniform and tunable mesoporous structure of NDCN is prepared using a templating approach. Such controlled in exerts an essential influence on electrocatalytic performance both alkaline acidic media ORR. The pore diameter 22 nm exhibits more positive ORR onset potential than that Pt/C (-0.01 V vs. -0.02 V) high diffusion-limited...

A cobalt-nitrogen-doped porous carbon that exhibits a ribbon-shape morphology, high surface area, mesoporous structure, and nitrogen cobalt content is fabricated for high-performance self-supported oxygen reduction electrocatalytsts through template-free pyrolysis of porphyrin-based conjugated polymer frameworks.

Graphene-based compact nanohybrid films made by alternate deposition of electrochemically exfoliated graphene and mesoporous graphene-conducting polymer nanosheets are constructed for high-energy micro-supercapacitors. They shown to have a landmark areal capacitance 368 mF cm(-2) volumetric 736 F cm(-3) .

Despite the intensive research efforts devoted to graphene fabrication over past decade, production of high-quality on a large scale, at an affordable cost, and in reproducible manner still represents great challenge. Here, we report novel method based controlled electrochemical exfoliation graphite aqueous ammonium sulfate electrolyte produce quantities with outstanding quality. Because radicals (e.g., HO(•)) generated from water electrolysis are responsible for defect formation during...

Heteroatom doping of nanocarbon films can efficiently boost the pseudocapacitance micro-supercapacitors (MSCs); however, wafer-scale fabrication sulfur-doped graphene with a tailored thickness and homogeneous for MSCs remains great challenge. Here we demonstrate bottom-up continuous, uniform, ultrathin (SG) films, derived from peripherical trisulfur-annulated hexa-peri-hexabenzocoronene (SHBC), ultrahigh-rate (SG-MSCs) landmark volumetric capacitance. The SG film was prepared by thermal...

Highly uniform, ultrathin, layer-by-layer heteroatom (N, B) co-doped graphene films are fabricated for high-performance on-chip planar micro-supercapacitors with an ultrahigh volumetric capacitance of ∼488 F cm−3 and excellent rate capability due to the synergistic effect nitrogen boron co-doping. As a service our authors readers, this journal provides supporting information supplied by authors. Such materials peer reviewed may be re-organized online delivery, but not copy-edited or typeset....

A novel solution fabrication of large-area, highly conductive graphene films by spray-coating a hybrid ink exfoliated (EG)/poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) (PH1000) is demonstrated. The fabricated exhibit excellent mechanical properties, thus enabling their application as bottom electrodes in ultrathin organic photodetector devices with performance comparable to that the state-of-the-art Si-based inorganic photodetectors.

Ultrathin printable graphene supercapacitors are demonstrated, based on solution-processed electrochemically exfoliated hybrid films an ultrathin poly(ethylene terephthalate) substrate, exhibiting unprecedented volumetric capacitance of 348 F cm(-3) , ultrahigh scan rate 2000 V s(-1) and AC line-filtering performance.

Abstract Nitrogen‐doped carbon nanosheets (NDCN) with size‐defined mesopores are reported as highly efficient metal‐free catalyst for the oxygen reduction reaction (ORR). A uniform and tunable mesoporous structure of NDCN is prepared using a templating approach. Such controlled in exerts an essential influence on electrocatalytic performance both alkaline acidic media ORR. The pore diameter 22 nm exhibits more positive ORR onset potential than that Pt/C (−0.01 V vs. −0.02 V) high...

Chemical functionalization is one of the most powerful and widely used strategies to control properties nanomaterials, particularly in field graphene. However, ill-defined structure present functionalized graphene inhibits atomically precise structural characterization structure-correlated property modulation. Here we a general edge chlorination protocol for nanographenes at different scales from 1.2 3.4 nm its application nanoribbons. The well-defined unambiguously confirmed by X-ray...

Stacked-layer heterostructure films of 2D thiophene nanosheets and electrochemically exfoliated graphene are constructed for ultrahigh-rate all-solid-state flexible pseudocapacitors micro-supercapacitors with superior volumetric capacitance due to the synergetic effect ultrathin pseudocapacitive capacitive graphene. As a service our authors readers, this journal provides supporting information supplied by authors. Such materials peer reviewed may be re-organized online delivery, but not...

Here we demonstrated the fabrication of ultrahigh rate, all-solid-state, planar interdigital graphene-based micro-supercapacitors (MSCs) manufactured by methane plasma-assisted reduction and photolithographic micro-fabrication graphene oxide films on silicon wafers. Notably, electrochemical performance MSCs is significantly enhanced increasing number fingers from 8 to 32 minimizing finger width 1175 219 μm, highlighting critical importance adjusting widths in high-performance MSCs. The...

This review article summarizes the latest progress in research regarding bioapplications of graphene oxide derivatives and provides expert opinions on strategies for overcoming current challenges.

Abstract The outstanding charge transport properties of graphene enable numerous electronic applications this remarkable material, many which are expected to operate at ultrahigh speeds. In the regime ultrafast, sub-picosecond electric fields, however, very high conduction not necessarily preserved, with physical picture explaining behaviour remaining unclear. Here we show that in graphene, on an ultrafast timescale is determined by a simple thermodynamic balance maintained within system...

Carbon-based films: Dopamine was used as the precursor for facile yet controllable production of a highly stretchable transparent conductive film (see picture). The synthesized is and can reversibly withstand mechanical deformations (such being stretched to 20 % 100 cycles).