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Lifeng Yan

Bio: Lifeng Yan is an academic researcher from University of Science and Technology of China. The author has contributed to research in topics: Graphene & Cellulose. The author has an hindex of 41, co-authored 192 publications receiving 8224 citations. Previous affiliations of Lifeng Yan include Chinese Academy of Sciences & Nanjing Medical University.


Papers
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01 Apr 2010-Carbon
TL;DR: In this article, a mild thermal reduction of graphene oxide (GO) to graphene was achieved with the assistance of microwaves in a mixed solution of N,N-dimethylacetamide and water (DMAc/H2O).

933 citations

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TL;DR: This work provides a general method to prepare 3D graphene/nanoparticle composites for a wide range of applications including catalysis and energy conversion.
Abstract: A 3D graphene architecture can be prepared via an in situ self-assembly of graphene prepared by a mild chemical reduction. Fe(3) O(4) nanoparticles are homogeneously dispersed into graphene oxide (GO) aqueous suspension and a 3D magnetic graphene/Fe(3) O(4) aerogel is prepared during the reduction of GO to graphene. This provides a general method to prepare 3D graphene/nanoparticle composites for a wide range of applications including catalysis and energy conversion.

822 citations

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TL;DR: A simple method for the preparation of 3D architectures of graphene via the in situ self-assembly of graphene prepared by mild chemical reduction at 95 °C under atmospheric pressure without stirring is developed.
Abstract: Three-dimensional (3D) architectures of graphene are of interest in applications in electronics, catalysis devices, and sensors. However, it is still a challenge to fabricate macroscopic all-graphene 3D architectures under mild conditions. Here, a simple method for the preparation of 3D architectures of graphene is developed via the in situself-assembly of graphene prepared by mild chemical reduction at 95 °C under atmospheric pressure without stirring. No chemical or physical cross-linkers or high pressures are required. The reducing agents include NaHSO3, Na2S, Vitamin C, HI, and hydroquinone. Both graphene hydrogels and aerogels can be prepared by this method, and the shapes of the 3D architectures can be controlled by changing the type of reactor. The 3D architectures of graphene have low densities, high mechanical properties, thermal stability, high electrical conductivity, and high specific capacitance, which make them candidates for potential applications in supercapacitors, hydrogen storage and as supports for catalysts.

663 citations

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TL;DR: In this article, aqueous solution of chitosan and graphene oxide in the present of diluted acetic acid was used to create a composite film with high tensile strength and high storage modulus up to 200°C.

473 citations

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TL;DR: Instead of hydrazine, a series of sulfur-containing compounds such as NaHSO3, Na2SO3 and Na2S2O3 were used as reducing agents to reduce graphene oxide to graphene.
Abstract: Instead of hydrazine, a series of sulfur-containing compounds such as NaHSO3, Na2SO3, Na2S2O3, Na2S·9H2O, SOCl2, and SO2, were used as reducing agents to reduce graphene oxide to graphene. Fourier transform infrared spectrometry, atomic force microscopy, X-ray photoelectron spectroscopy, Raman spectroscopy, elemental analysis, and thermogravimetric analysis confirmed the formation of graphene under chemical reduction at 95 °C. The results reveal that the reducing ability of NaHSO3 is comparable to that of hydrazine. This newly found reducing agent is of low toxicity and nonvolatile, which makes the reduction much safer than hydrazine. A possible mechanism of the reduction has been suggested. The electrical conductivity of the graphene paper prepared using a NaHSO3 reducing agent is found to be 6500 S m−1, while it is observed to be 5100 S m−1 for hydrazine-reduced graphene paper. These studies also confirmed that SOCl2 can be a good candidate as a reducing agent to compete with hydrazine.

467 citations


Cited by
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TL;DR: A critical review of the synthesis methods for graphene and its derivatives as well as their properties and the advantages of graphene-based composites in applications such as the Li-ion batteries, supercapacitors, fuel cells, photovoltaic devices, photocatalysis, and Raman enhancement are described.
Abstract: Graphene has attracted tremendous research interest in recent years, owing to its exceptional properties. The scaled-up and reliable production of graphene derivatives, such as graphene oxide (GO) and reduced graphene oxide (rGO), offers a wide range of possibilities to synthesize graphene-based functional materials for various applications. This critical review presents and discusses the current development of graphene-based composites. After introduction of the synthesis methods for graphene and its derivatives as well as their properties, we focus on the description of various methods to synthesize graphene-based composites, especially those with functional polymers and inorganic nanostructures. Particular emphasis is placed on strategies for the optimization of composite properties. Lastly, the advantages of graphene-based composites in applications such as the Li-ion batteries, supercapacitors, fuel cells, photovoltaic devices, photocatalysis, as well as Raman enhancement are described (279 references).

3,340 citations

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TL;DR: Graphene and its derivatives are being studied in nearly every field of science and engineering as mentioned in this paper, and recent progress has shown that the graphene-based materials can have a profound impact on electronic and optoelectronic devices, chemical sensors, nanocomposites and energy storage.

3,118 citations

Journal ArticleDOI
18 Jul 2011-Small
TL;DR: The synthesis, characterization, properties, and applications of graphene-based materials are discussed and the promising properties together with the ease of processibility and functionalization make graphene- based materials ideal candidates for incorporation into a variety of functional materials.
Abstract: Graphene, a two-dimensional, single-layer sheet of sp(2) hybridized carbon atoms, has attracted tremendous attention and research interest, owing to its exceptional physical properties, such as high electronic conductivity, good thermal stability, and excellent mechanical strength. Other forms of graphene-related materials, including graphene oxide, reduced graphene oxide, and exfoliated graphite, have been reliably produced in large scale. The promising properties together with the ease of processibility and functionalization make graphene-based materials ideal candidates for incorporation into a variety of functional materials. Importantly, graphene and its derivatives have been explored in a wide range of applications, such as electronic and photonic devices, clean energy, and sensors. In this review, after a general introduction to graphene and its derivatives, the synthesis, characterization, properties, and applications of graphene-based materials are discussed.

2,246 citations

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TL;DR: In this paper, the effect of nanostructures on the properties of supercapacitors including specific capacitance, rate capability and cycle stability is discussed, which may serve as a guideline for the next generation of super-capacitor electrode design.
Abstract: Supercapacitors have drawn considerable attention in recent years due to their high specific power, long cycle life, and ability to bridge the power/energy gap between conventional capacitors and batteries/fuel cells. Nanostructured electrode materials have demonstrated superior electrochemical properties in producing high-performance supercapacitors. In this review article, we describe the recent progress and advances in designing nanostructured supercapacitor electrode materials based on various dimensions ranging from zero to three. We highlight the effect of nanostructures on the properties of supercapacitors including specific capacitance, rate capability and cycle stability, which may serve as a guideline for the next generation of supercapacitor electrode design.

1,987 citations

Journal ArticleDOI
TL;DR: It is found that Fe(3)O(4)/N-GAs show a more positive onset potential, higher cathodic density, lower H(2)O-2) yield, and higher electron transfer number for the ORR in alkaline media than Fe( 3)O (4) NPs supported on N-doped carbon black or N- doped graphene sheets, highlighting the importance of the 3D macropores and high specific surface area of the GA support for
Abstract: Three-dimensional (3D) N-doped graphene aerogel (N-GA)-supported Fe3O4 nanoparticles (Fe3O4/N-GAs) as efficient cathode catalysts for the oxygen reduction reaction (ORR) are reported. The graphene hybrids exhibit an interconnected macroporous framework of graphene sheets with uniform dispersion of Fe3O4 nanoparticles (NPs). In studying the effects of the carbon support on the Fe3O4 NPs for the ORR, we found that Fe3O4/N-GAs show a more positive onset potential, higher cathodic density, lower H2O2 yield, and higher electron transfer number for the ORR in alkaline media than Fe3O4 NPs supported on N-doped carbon black or N-doped graphene sheets, highlighting the importance of the 3D macropores and high specific surface area of the GA support for improving the ORR performance. Furthermore, Fe3O4/N-GAs show better durability than the commercial Pt/C catalyst.

1,952 citations