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Showing papers by "Nanjing University of Science and Technology published in 2012"


Journal ArticleDOI
16 Feb 2012-Sensors
TL;DR: The gait analysis methods based on wearable sensors is divided into gait kinematics, gait kinetics, and electromyography, which are expected to play an increasingly important role in clinical applications.
Abstract: Gait analysis using wearable sensors is an inexpensive, convenient, and efficient manner of providing useful information for multiple health-related applications. As a clinical tool applied in the rehabilitation and diagnosis of medical conditions and sport activities, gait analysis using wearable sensors shows great prospects. The current paper reviews available wearable sensors and ambulatory gait analysis methods based on the various wearable sensors. After an introduction of the gait phases, the principles and features of wearable sensors used in gait analysis are provided. The gait analysis methods based on wearable sensors is divided into gait kinematics, gait kinetics, and electromyography. Studies on the current methods are reviewed, and applications in sports, rehabilitation, and clinical diagnosis are summarized separately. With the development of sensor technology and the analysis method, gait analysis using wearable sensors is expected to play an increasingly important role in clinical applications.

926 citations


Journal ArticleDOI
TL;DR: Unique features of lens-free computational imaging tools are discussed and some of their emerging results for wide-field on-chip microscopy, such as the achievement of a numerical aperture of ∼0.8–0.9 across a field of view (FOV) of more than 20 mm2, which corresponds to an image with more than 1.5 gigapixels.
Abstract: In this perspective, the authors present the basic features of lens-free computational imaging tools and report performance comparisons with conventional microscopy methods. They also discuss the challenges that these computational on-chip microscopes face for their wide-scale biomedical application.

486 citations


Journal ArticleDOI
TL;DR: The superior supercapacitive performance of the MnO2/CNT nancomposite electrode is due to its high specific surface area and unique hierarchy architecture which facilitate fast electron and ion transport.
Abstract: MnO2/carbon nanotube [CNT] nanocomposites with a CNT core/porous MnO2 sheath hierarchy architecture are synthesized by a simple hydrothermal treatment. X-ray diffraction and Raman spectroscopy analyses reveal that birnessite-type MnO2 is produced through the hydrothermal synthesis. Morphological characterization reveals that three-dimensional hierarchy architecture is built with a highly porous layer consisting of interconnected MnO2 nanoflakes uniformly coated on the CNT surface. The nanocomposite with a composition of 72 wt.% (K0.2MnO2·0.33 H2O)/28 wt.% CNT has a large specific surface area of 237.8 m2/g. Electrochemical properties of the CNT, the pure MnO2, and the MnO2/CNT nanocomposite electrodes are investigated by cyclic voltammetry and electrochemical impedance spectroscopy measurements. The MnO2/CNT nanocomposite electrode exhibits much larger specific capacitance compared with both the CNT electrode and the pure MnO2 electrode and significantly improves rate capability compared to the pure MnO2 electrode. The superior supercapacitive performance of the MnO2/CNT nancomposite electrode is due to its high specific surface area and unique hierarchy architecture which facilitate fast electron and ion transport.

427 citations


Journal ArticleDOI
TL;DR: A novel strategy for spatially controlled functionalization of AuNPs with designed diblock oligonucleotides that are free of modifications is reported, which results in DNA-AuNPs nanoconjugates with high and tunable hybridization ability, which form the basis of a rapid plasmonic DNA sensor.
Abstract: Conjugates of DNA and gold nanoparticles (AuNPs) typically exploit the strong Au–S chemistry to self-assemble thiolated oligonucleotides at AuNPs. However, it remains challenging to precisely control the orientation and conformation of surface-tethered oligonucleotides and finely tune the hybridization ability. We herein report a novel strategy for spatially controlled functionalization of AuNPs with designed diblock oligonucleotides that are free of modifications. We have demonstrated that poly adenine (polyA) can serve as an effective anchoring block for preferential binding with the AuNP surface, and the appended recognition block adopts an upright conformation that favors DNA hybridization. The lateral spacing and surface density of DNA on AuNPs can also be systematically modulated by adjusting the length of the polyA block. Significantly, this diblock oligonucleotide strategy results in DNA–AuNPs nanoconjugates with high and tunable hybridization ability, which form the basis of a rapid plasmonic DNA...

426 citations


Journal ArticleDOI
TL;DR: In this article, a straightforward strategy was designed for the fabrication of magnetically separable CoFe2O4-graphene photocatalysts with differing graphene content, and the significant enhancement in photoactivity under visible-light irradiation can be ascribed to reduction of graphene oxide, because the photogenerated electrons of CoFeO4 can transfer easily from the conduction band to the reduced graphene oxide effectively preventing a direct recombination of electrons and holes.
Abstract: A straightforward strategy was designed for the fabrication of magnetically separable CoFe2O4-graphene photocatalysts with differing graphene content. It is very interesting that the combination of CoFe2O4 nanoparticles with graphene results in a dramatic conversion of the inert CoFe2O4 into a highly active catalyst for the degradation of methylene blue (MB), Rhodamine B (RhB), methyl orange (MO), active black BL-G and active red RGB under visible-light irradiation. The significant enhancement in photoactivity under visible-light irradiation can be ascribed to reduction of graphene oxide, because the photogenerated electrons of CoFe2O4 can transfer easily from the conduction band to the reduced graphene oxide, effectively preventing a direct recombination of electrons and holes. Hydroxyl radicals play the role of main oxidant in the CoFe2O4-graphene system and the radicals’ oxidation reaction is obviously dominant. CoFe2O4 nanoparticles themselves have a strong magnetic property, which can be used for magnetic separation in a suspension system, and therefore the introduction of additional magnetic supports is no longer necessary.

339 citations


Journal ArticleDOI
TL;DR: A lensfree on-chip imaging technique that can track the three-dimensional trajectories of > 1,500 individual human sperms within an observation volume of approximately 8–17 mm3 and could in general be quite valuable for observing the statistical swimming patterns of various other microorganisms, leading to new insights in their 3D motion and the underlying biophysics.
Abstract: Dynamic tracking of human sperms across a large volume is a challenging task. To provide a high-throughput solution to this important need, here we describe a lensfree on-chip imaging technique that can track the three-dimensional (3D) trajectories of > 1,500 individual human sperms within an observation volume of approximately 8–17 mm3. This computational imaging platform relies on holographic lensfree shadows of sperms that are simultaneously acquired at two different wavelengths, emanating from two partially-coherent sources that are placed at 45° with respect to each other. This multiangle and multicolor illumination scheme permits us to dynamically track the 3D motion of human sperms across a field-of-view of > 17 mm2 and depth-of-field of approximately 0.5–1 mm with submicron positioning accuracy. The large statistics provided by this lensfree imaging platform revealed that only approximately 4–5% of the motile human sperms swim along well-defined helices and that this percentage can be significantly suppressed under seminal plasma. Furthermore, among these observed helical human sperms, a significant majority (approximately 90%) preferred right-handed helices over left-handed ones, with a helix radius of approximately 0.5–3 μm, a helical rotation speed of approximately 3–20 rotations/s and a linear speed of approximately 20–100 μm/s. This high-throughput 3D imaging platform could in general be quite valuable for observing the statistical swimming patterns of various other microorganisms, leading to new insights in their 3D motion and the underlying biophysics.

339 citations


Journal ArticleDOI
TL;DR: In this paper, a symmetric RuO2/RuO2 supercapacitor with a high operating voltage of 1.6 V is built using the nanocrystalline hydrous RuO 2.
Abstract: A novel symmetric RuO2/RuO2 supercapacitor with a high operating voltage of 1.6 V is built using the nanocrystalline hydrous RuO2. The symmetric supercapacitor exhibits an energy density of 18.77 Wh kg −1 at a power density of 500 W kg −1 based on the total mass of active electrode material and excellent cycling stability and power capability. These results demonstrate the potentialities of using RuO2 for symmetric supercapacitor or using RuO2 as negative electrode for asymmetric supercapacitor with high energy density.

324 citations


Journal ArticleDOI
01 Dec 2012
TL;DR: It is shown that the designed controller can guarantee all the signals in the closed-loop system to be semiglobally uniformly ultimately bounded in a mean square.
Abstract: This paper focuses on the problem of neural-network-based decentralized adaptive output-feedback control for a class of nonlinear strict-feedback large-scale stochastic systems. The dynamic surface control technique is used to avoid the explosion of computational complexity in the backstepping design process. A novel direct adaptive neural network approximation method is proposed to approximate the unknown and desired control input signals instead of the unknown nonlinear functions. It is shown that the designed controller can guarantee all the signals in the closed-loop system to be semiglobally uniformly ultimately bounded in a mean square. Simulation results are provided to demonstrate the effectiveness of the developed control design approach.

284 citations


Journal ArticleDOI
TL;DR: Analysis of the distributed containment control problem for a group of autonomous vehicles modeled by double-integrator dynamics with multiple dynamic leaders shows that the followers will move into the convex hull spanned by the dynamic leaders if the network topology among the followers is undirected.
Abstract: This note studies the distributed containment control problem for a group of autonomous vehicles modeled by double-integrator dynamics with multiple dynamic leaders. The objective is to drive the followers into the convex hull spanned by the dynamic leaders under the constraints that the velocities and the accelerations of both the leaders and the followers are not available, the leaders are neighbors of only a subset of the followers, and the followers have only local interaction. Two containment control algorithms via only position measurements of the agents are proposed. Theoretical analysis shows that the followers will move into the convex hull spanned by the dynamic leaders if the network topology among the followers is undirected, for each follower there exists at least one leader that has a directed path to the follower, and the parameters in the algorithm are properly chosen. Numerical results are provided to illustrate the theoretical results.

274 citations


Journal ArticleDOI
TL;DR: Two multiattribute decision‐making methods are developed in which the attribute values are given in the form of hesitant fuzzy sets reflecting humans' hesitant thinking comprehensively, and it is found that three measures are interchangeable under certain conditions.
Abstract: We introduce the concepts of entropy and cross-entropy for hesitant fuzzy information, and discuss their desirable properties. Several measure formulas are further developed, and the relationships among the proposed entropy, cross-entropy, and similarity measures are analyzed, from which we can find that three measures are interchangeable under certain conditions. Then we develop two multiattribute decision-making methods in which the attribute values are given in the form of hesitant fuzzy sets reflecting humans' hesitant thinking comprehensively. In one method, the weight vector is determined by the hesitant fuzzy entropy measure, and the optimal alternative is obtained by comparing the hesitant fuzzy cross-entropies between the alternatives and the ideal solutions; in another method, the weight vector is derived from the maximizing deviation method and the optimal alternative is obtained by using the TOPSIS method. An actual example is provided to compare our methods with the existing ones. © 2012 Wiley Periodicals, Inc. © 2012 Wiley Periodicals, Inc.

274 citations


Journal ArticleDOI
TL;DR: The iodine catalyzed oxidative system for 3-sulfenylation of indoles with disulfides using DMSO as oxidant has been achieved under ambient conditions, providing a convenient and efficient method for the synthesis of 3-methine-based indoles in good to excellent yields and with high selectivity.

Journal ArticleDOI
TL;DR: In this article, a critical review on the recent development of novel narrow bandgap polymers for high-efficiency polymer solar cells concentrates on the structural design of narrow band gap polymers, which occupy a central place in recent advances in high efficiency polysilicon solar cells, the intrinsic physics and chemistry of special properties, such as absorption, bandgap and energy levels, and correlation of polymer structure and device fabrication with their photovoltaic performances.

Journal ArticleDOI
TL;DR: The CCFV removes the constraint of static camera array settings for view capturing and can be applied to any view-based 3-D object database and experimental results show that the proposed scheme can achieve better performance than state-of-the-art methods.
Abstract: Recently, extensive research efforts have been dedicated to view-based methods for 3-D object retrieval due to the highly discriminative property of multiviews for 3-D object representation. However, most of state-of-the-art approaches highly depend on their own camera array settings for capturing views of 3-D objects. In order to move toward a general framework for 3-D object retrieval without the limitation of camera array restriction, a camera constraint-free view-based (CCFV) 3-D object retrieval algorithm is proposed in this paper. In this framework, each object is represented by a free set of views, which means that these views can be captured from any direction without camera constraint. For each query object, we first cluster all query views to generate the view clusters, which are then used to build the query models. For a more accurate 3-D object comparison, a positive matching model and a negative matching model are individually trained using positive and negative matched samples, respectively. The CCFV model is generated on the basis of the query Gaussian models by combining the positive matching model and the negative matching model. The CCFV removes the constraint of static camera array settings for view capturing and can be applied to any view-based 3-D object database. We conduct experiments on the National Taiwan University 3-D model database and the ETH 3-D object database. Experimental results show that the proposed scheme can achieve better performance than state-of-the-art methods.

Journal ArticleDOI
TL;DR: In this article, a magnetic nanoparticle supported dual acidic ionic liquid catalyst was synthesized by anchoring 3-sulfobutyl-1-(3-propyltriethoxysilane) imidazolium hydrogen sulfate onto the surface of silica-coated Fe3O4 nanoparticles.

Journal ArticleDOI
TL;DR: Bacterial cellulose (BC) nanofiber-supported polyaniline (PANI) nanocomposites have been synthesized via in situ polymerization of aniline onto BC nanofibers scalfold as mentioned in this paper.
Abstract: Bacterial cellulose (BC) nanofiber-supported polyaniline (PANI) nanocomposites have been synthesized via in situ polymerization of aniline onto BC nanofibers scalfold. Optimized preparation conditi...

Journal ArticleDOI
TL;DR: In this paper, a ternary composite of polyaniline and Fe2O3 nanoparticles is presented, which exhibits a high specific capacitance of 638 F g−1 in 1 M KOH at a scan rate of 1 mV s−1.
Abstract: Well-designed nanostructures of a ternary nanocomposite, graphene/Fe2O3/polyaniline, are fabricated via a two-step approach. Graphene oxide is reduced by Fe2+ and well-dispersed by loading α-Fe2O3 nanoparticles (20–70 nm in size). A thin film of polyaniline is in situ polymerized on the graphene/Fe2O3 surfaces for the fabrication of its ternary composite. Among the composites obtained at different ratios of graphene/Fe2O3 to polyaniline, the ternary graphene/Fe2O3/polyaniline with a ratio of 2 : 1 exhibits a high specific capacitance of 638 F g−1 in 1 M KOH at a scan rate of 1 mV s−1 and experiences only a negligible decay of 8% after 5000 cycles. It also shows a higher energy density at high power density than other ternary or binary composites of the three components, respectively. The extraordinary electrochemical performance of the composite arises from the well-designed structural advantages of the ternary nanocomposite, and the good combination and synergistic effects among the three components. Graphene sheets, as the conducting frameworks for sustaining polyaniline and Fe2O3, can separate and disperse well in the composite due to the existence of Fe2O3. On the other hand, the thin film of polyaniline on the surface of graphene/Fe2O3 not only enhances the surface area, but also restricts the dissolution, aggregation and volume changes of Fe2O3 during charge–discharge cycling. Additionally, the existence of Fe2O3 is helpful to increase the rate stability of the ternary composite. The ternary composites with synergistic effects can take advantage of both Faradaic and non-Faradaic processes for capacity-charge storage with excellent electrochemical properties.

Journal ArticleDOI
TL;DR: An insight into the newly-emerging sparse representation-based classifier (SRC) is given and reasonable supports for its effectiveness are sought and it is found that for pattern recognition tasks, L"1- Optimizer provides more classification meaningful information than L"0-optimizer does.

Journal ArticleDOI
TL;DR: An easy-to-implement three-dimensional (3-D) real-time shape measurement technique using the authors' newly developed high-speed 3-D vision system that employs only four projection fringes to realize full-field phase unwrapping in the presence of discontinuous or isolated objects.
Abstract: This paper describes an easy-to-implement three-dimensional (3-D) real-time shape measurement technique using our newly developed high-speed 3-D vision system. It employs only four projection fringes to realize full-field phase unwrapping in the presence of discontinuous or isolated objects. With our self-designed pattern generation hardware and a modified low-cost DLP projector, the four designed patterns can be generated and projected at a switching speed of 360 Hz. Using a properly synchronized high-speed camera, the high-speed fringe patterns distorted by measured objects can be acquired and processed in real-time. The resulting system can capture and display high-quality textured 3-D data at a speed of 120 frames per second, with the resolution of 640 × 480 points. The speed can be trebled if a camera with a higher frame rate is employed. We detail our shape measurement technique, including the four-pattern decoding algorithm as well as the hardware design. Some evaluation experiments have been carried out to demonstrate the validity and practicability of the proposed technique.

Journal ArticleDOI
TL;DR: In this paper, a straightforward hydrothermal strategy is designed for the fabrication of CoFe2O4-graphene nanocomposites with different graphene contents, which exhibit promising electrochemical performance as anode material for lithium-ion batteries.

Journal ArticleDOI
TL;DR: In this article, a straightforward strategy is designed for the fabrication of CuFe2O4-graphene heteroarchitecture via a one-step hydrothermal route to allow multifunctional properties, i.e., magnetic cycling, high photocatalytic activity under visible light irradiation, and excellent electrochemical behaviors for use as the anode in lithium-ion batteries (LIBs).
Abstract: A straightforward strategy is designed for the fabrication of CuFe2O4-graphene heteroarchitecture via a one-step hydrothermal route to allow multifunctional properties, i.e., magnetic cycling, high photocatalytic activity under visible light irradiation, and excellent electrochemical behaviors for use as the anode in lithium-ion batteries (LIBs). Transmission electron microscopy (TEM) observations indicate that graphene sheets are exfoliated and decorated with hexagonal CuFe2O4 nanoflakes. The photocatalytic activity measurements demonstrate that the combination of CuFe2O4 and graphene results in a dramatic conversion of the inert CuFe2O4 into a highly active catalyst for the degradation of methylene blue (MB) under visible light irradiation. CuFe2O4 nanoparticles themselves have excellent magnetic properties, which makes the CuFe2O4-graphene heteroarchitecture magnetically recyclable in a suspension system. It should be pointed out that the CuFe2O4-graphene (with 25 wt % graphene) heteroarchitecture as a...

Journal ArticleDOI
TL;DR: In this article, a cobalt ferrite-polyaniline photocatalyst is successfully prepared by in situ oxidative polymerization, and a significant adsorption can be observed in the case of the anionic dyes and neutral dyes because the negatively charged groups or the electron-rich groups of these dyes undergo chemical interactions with the positively charged backbone of PANI.
Abstract: A cobalt ferrite–polyaniline photocatalyst is successfully prepared by in situ oxidative polymerization. The excellent magnetic properties of CoFe2O4 are maintained in the composite to some extent, and therefore the photocatalyst can be separated easily by an external magnetic field. A significant adsorption can be observed in the case of the anionic dyes and neutral dyes because the negatively charged groups or the electron-rich groups of these dyes undergo chemical interactions with the positively charged backbone of polyaniline (PANI). Such an adsorption helps in promoting the photodegradation of the dyes. It is interesting that although CoFe2O4 alone is an inactive visible-light-driven photocatalyst, the combination of CoFe2O4 nanoparticles with PANI leads to high photocatalytic activity for the degradation of the dyes under visible light irradiation. The dramatic enhancement in photoactivity can be attributed to the excited state electrons in PANI which can migrate to the conduction band (CB) of CoFe2O4, and the photogenerated holes in the valence band (VB) of CoFe2O4 which can directly transfer to the HOMO of PANI, effectively preventing a direct recombination of electrons and holes. Due to electrostatic repulsion, the cationic dyes containing positively charged groups cannot easily gain access to the positively charged backbone of PANI, giving very low photodegradation rates.

Journal ArticleDOI
TL;DR: In this paper, a ternary electrode material based on graphene, tin oxide (SnO2) and polypyrrole (PPy) was obtained via one-pot synthesis.
Abstract: A ternary electrode material, based on graphene, tin oxide (SnO2) and polypyrrole (PPy) was obtained via one–pot synthesis. The graphene/SnO2/PPy (GSP) nanocomposite is composed of a thin conducting film of PPy on the surface of graphene/SnO2 (GS). An enhanced specific capacitance (616 F g−1) of GSP was obtained at 1 mV s−1 in 1 M H2SO4 compared with GS (80.2 F g−1) and PPy (523 F g−1). The GSP electrode shows better cycle stability and no obvious decay after 1000 galvanostatic cycles at 1 A g−1. Its specific power density and energy density can reach 9973.26 W kg−1, and 19.4 W h kg−1, respectively. The excellent electrochemical performance arises from the well-designed structure advantages, the good combination of components and the synergistic effect between the three components. Well-dispersed graphene is used as a framework for sustaining the pseudocapacitive materials of SnO2 and PPy. The PPy film restricts the aggregation and volume change of SnO2 during charge–discharge cycling, and also enhances the surface area. The electrochemical results show that the ternary composite of GSP is a promising candidate electrode material for high-performance supercapacitors.

Journal ArticleDOI
TL;DR: Li 4 Ti 4.95 La 0.05 O 12 (LTO) material was synthesized by a simple solid-state method at air as discussed by the authors, and the obtained Li 4 Ti 5− x La 2/3− x TiO 3 (LLTO) solid solution was well crystallized with a particle size in the range of 1-2μm.

Journal ArticleDOI
TL;DR: In this paper, structural, electronic, and magnetic properties of the graphene-like ZnO monolayer doped with nonmetal species using the first-principles calculations were studied.
Abstract: We have studied structural, electronic, and magnetic properties of the graphene-like ZnO monolayer doped with nonmetal species using the first-principles calculations. Particular attention has been...

Journal ArticleDOI
TL;DR: In this paper, a poly(3,4-ethylenedioxy-thiophene) (PEDOT)/graphene oxide (GO) hybrid film was directly electrodeposited on a glassy carbon electrode.

Journal ArticleDOI
TL;DR: In this article, a simple and straightforward strategy was developed to fabricate magnetically separable MnFe2O4-graphene photocatalysts with differing graphene content.
Abstract: A simple and straightforward strategy was developed to fabricate magnetically separable MnFe2O4–graphene photocatalysts with differing graphene content. It was found that graphene sheets were fully exfoliated and decorated with MnFe2O4 nanocrystals having an average diameter of 5.65 nm and a narrow particle size distribution. It is very interesting that, although MnFe2O4 alone is photocatalytically inactive under visible light irradiation, the combination of MnFe2O4 nanoparticles with graphene sheets leads to high photocatalytic activity for the degradation of methylene blue under visible light irradiation. The strong magnetic property of MnFe2O4 nanoparticles can be used for magnetic separation in a suspension system, and therefore it does not require additional magnetic components as is the usual case. Consequently, the MnFe2O4–graphene system becomes a dual function photocatalyst. The significant enhancement in photoactivity under visible light irradiation can be ascribed to the reduction of graphene o...

Journal ArticleDOI
TL;DR: In this article, a planar ultrawideband (UWB) antenna with dual notched bands is proposed and investigated, where a T-shaped stub embedded in the square slot of the radiation patch and a pair of U-shaped parasitic strips beside the feed line is used.
Abstract: A novel planar ultrawideband (UWB) antenna with dual notched bands is proposed and investigated. The antenna consists of a square patch and a modified grounded plane. To realize dual notched bands characteristics, a T-shaped stub embedded in the square slot of the radiation patch and a pair of U-shaped parasitic strips beside the feed line is used. The advantage of this antenna is the high rejection level in the stopband. The measured results show that the proposed dual-notched-bands planar antenna shows a very wide bandwidth from 2.8 to 11.0 GHz defined by voltage standing wave ratio VSWR <; 2, with two notched bands of 3.3-4.0 GHz (WiMAX band) and 5.05-5.90 GHz (WLAN band), respectively. Both the experimental and simulated results of the proposed antenna are presented, indicating that the antenna is a good candidate for various UWB applications.

Journal ArticleDOI
TL;DR: In this article, a soft chemical method has been developed to load Pt nanoparticles on graphene nanoplates (GNPs) without damaging their graphene structures, which shows that the GNPs can be used as promising electrocatalyst supports for direct methanol fuel cells.

Journal ArticleDOI
TL;DR: In this paper, a well-dispersed Pd nanoparticles supported on low-defect graphene (LDG) sheets are successfully prepared by a soft chemical method, which can efficiently avoid damaging the graphene framework in the composite because it does not require cumbersome oxidation of graphite in advance and needs no subsequent reduction of the LDG sheets due to the lower oxidation degree.
Abstract: Well-dispersed Pd nanoparticles supported on low-defect graphene (LDG) sheets are successfully prepared by a soft chemical method. Our approach can efficiently avoid damaging the graphene framework in the composite because it does not require cumbersome oxidation of graphite in advance and needs no subsequent reduction of the LDG sheets due to the lower oxidation degree. Morphology observations show that the Pd nanoparticles with diameters ranging from 1 to 5 nm are evenly deposited on graphene sheets. Raman spectroscopic analysis results reveals that there is only a very small amount of graphene defects in the hybrid. No matter whether it is for a direct formic acid fuel cell (DFAFC) or direct methanol fuel cell (DMFC), the LDG-supported Pd catalyst has very large electrochemically active surface area (ECSA) values, more than twice as large as that for the reduced graphene oxide, or five times the commercial XC-72 carbon. The forward peak current measurements show similar results. The excellent catalytic performance of LDG/Pd can be attributed to the preserved pristine graphene structure, which not only provides a lot of surface area for the deposition of nanoparticles, but also allows for electrical conductivity and stability in the composite.

Journal ArticleDOI
TL;DR: In this paper, the reduced-graphene oxide/molybdenum oxide/polyaniline ternary composites, RGO(MP)8, were firstly synthesized using a one-step method with Mo3O10(C6H8N)2·2H2O and graphene oxide (GO) as precursors.
Abstract: Reduced-graphene oxide/molybdenum oxide/polyaniline ternary composites, RGO(MP), for use as electrode materials for high energy density supercapacitors, were firstly synthesized using a one-step method with Mo3O10(C6H8N)2·2H2O and graphene oxide (GO) as precursors. When the mass ratio of Mo3O10(C6H8N)2·2H2O to GO is 8 : 1, the resulting composite RGO(MP)8 shows excellent electrochemical performance with a maximum specific capacitance of 553 F g−1 in 1M H2SO4 and 363 F g−1 in 1 M Na2SO4 at a scan rate of 1 mV s−1. Its energy density reaches 76.8 W h kg−1 at a power density of 276.3 W kg−1, and 28.6 W h kg−1 at a high power density of 10294.3 W kg−1 in H2SO4. While in Na2SO4, the energy density achieves 72.6 W h Kg−1 at a power density of 217.7 W kg−1 and 13.3 W h Kg−1 at power density of 3993.8 W kg−1, respectively. The composite also presents good cycling stability (86.6, 73.4% at 20 mV s−1 after 200 cycles in 1 M H2SO4 and Na2SO4, respectively).