Nanoparticles Embedded Carbon Nanofibers Research Articles

Regulating Hydrogen/Oxygen Species Adsorption via Built-in Electric Field -Driven Electron Transfer Behavior at the Heterointerface for Efficient Water Splitting.

Alkaline water electrolysis (AWE) plays a crucial role in the realization of a hydrogen economy. The design and development of efficient and stable bifunctional catalysts for both the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) are pivotal to achieving high-efficiency AWE. Herein, WC1-x/Mo2C nanoparticle-embedded carbon nanofiber (WC1-x/Mo2C@CNF) with abundant interfaces is successfully designed and synthesized. Benefiting from the electron transfer behavior from Mo2C to WC1-x, the electrocatalysts of WC1-x/Mo2C@CNF exhibit superior HER and OER performance. Furthermore, when employed as anode and cathode in membrane electrode assembly devices, the WC1-x/Mo2C@CNF catalyst exhibits enhanced catalytic activity and remarkable stability for 100 hours at a high current density of 200 mA cm-2 towards overall water splitting. The experimental characterizations and theoretical simulation reveal that modulation of the d-band center for WC1-x/Mo2C@CNF, achieved through the asymmetric charge distribution resulting from the built-in electric field induced by work function, enables optimization of adsorption strength for hydrogen/oxygen intermediates, thereby promoting the catalytic kinetics for overall water splitting. This work provides promising strategies for designing highly active catalysts in energy conversion fields.

Preparation and characterization of palladium nanoparticle-embedded carbon nanofiber membranes via electrospinning and carbonization strategy.

Carbon nanofiber membranes (CNMs) are expected to be used in many energy devices to improve the reaction rate. In this paper, CNMs embedded with palladium nanoparticles (Pd-CNMs) were prepared by electrospinning and carbonization using polyimide as the raw material. The effects of carbonization temperature, carbonization atmosphere, and heating rate on the physicochemical properties of the as-obtained Pd-CNMs were studied in detail. On this basis, the electrocatalytic performance of Pd-CNMs prepared under optimal conditions was characterized. The results showed that highly active zero-valent palladium nanoparticles with uniform particle size could be distributed on the surface of carbon nanofibers. Under vacuum conditions, at a carbonization temperature of 800 °C and a heating rate of 2 °C min-1, Pd-CNMs have lower H2O2 yield, lower Tafel slope (73.3 mV dec-1), higher electron transfer number (∼4), and superior durability, suggesting that Pd-CNMs exhibit excellent electrocatalytic activity for ORR in alkaline electrolyte. Therefore, polyimide-derived CNMs embedded with Pd nanoparticles are expected to become an excellent cathode catalyst layer for fuel cells.

Efficient Polysulfides Conversion Kinetics Enabled by Ni@CNF Interlayer for Lithium Sulfur Batteries

Recent advances in the development of lithium-sulfur batteries (Li-S) demonstrated their high effectiveness owing to their tremendous theoretical specific capacity and high theoretical gravimetrical energy. Nevertheless, the potential commercialization of Li-S is significantly held by the insulating nature of sulfur and complicated RedOx reactions during the electrochemical charge-discharge processes. This paper presents nickel nanoparticles embedded carbon nanofibers interlayer (Ni@CNF) between a cathode and a separator as an additional physical barrier against lithium polysulfides shuttle for their efficient conversion during the charge-discharge cycling. Furthermore, the interlayer provides an auxiliary electron pathway with subsequent lowering of the charge transfer resistance. The electrochemical analysis of a Li-S cell with the Ni@CNF interlayer demonstrated high initial discharge capacities of 1441.2 mAh g-1 and 1194.2 mAh g-1 at 0.1 and 1.0 C rates, respectively, with remarkable capacity retention of ~83% after 100 cycles. This study revealed the advantageous impact of Ni@CNF towards solving the major issues of lithium-sulfur batteries, i.e., sluggish kinetics and the shuttle effect.

Iron nanoparticle embedded carbon nanofibers as flexible electrodes for selective chloride ions capture in capacitive deionization

Developing steady material for selective chloride ion capture is a challenging task to match the high capacity of counterparts during the practice of capacitive deionization (CDI). Iron-based materials have presented great potential for its environmentally friendly and low-cost features as chloride ion trapping electrodes. However, the severe capacity fading occurs due to the uncontrollable aggregation during cycling. Herein, iron nanoparticles embedded carbon fibers are creatively fabricated via an electrospinning technology followed by an anneal treatment. The presence of iron greatly increases the capacity of the electrode, while the coating structure of carbon nanofibers improves stability. Due to the synergistic effect of the electric double layer and the pseudocapacitance behavior, when employed as an anode for capacitive deionization device, this material shows an excellent adsorption capacity (82.5 mg g−1) and fast adsorption rate (20.4 mg g−1 min−1) during the desalting process. Meanwhile, the carbon-coated structure greatly prevents the dissolution or aggregation of iron nanoparticles in the reaction process, so that the electrode displays a splendid cycle stability and there is still a 93 % capacity retention rate after 30 cycles. In short, this work provides a new strategy for capacitive desalination of chloride ion trapping electrode with excellent performance by means of encapsulating iron nanoparticles into carbon nanofibers.

Metal Doped Carbon Nanofiber for Ratio Tunable Syngas Catalyst By CO2 Reduction

Due to the influence of human beings in the modern society, the concentration of CO2 in the atmosphere is rapidly increasing, which causes various environmental problems such as abnormal climate caused by global warming and destruction of ecosystem due to ocean acidification. Therefore, many institutional, scientific, and engineering efforts are being made to reduce the concentration of CO2 in the atmosphere. From the scientific point of view, to make the fuels and chemicals we need from the atmospheric CO2, electrochemical reduction of CO2 is actively being studied. The electrochemical CO2 reduction reaction can be divided into two categories, one for synthesizing multi-carbon products directly such as ethylene or ethanol and the other for producing syngas mixed with CO and H2. The former is mainly researched on Cu based material and has an advantage in that the desired product can be obtained immediately. In the latter case, by adjusting the ratio of CO and H2 in the synthesis gas, it is possible to synthesize multi-carbon products. The latter method can be said to have an advantage in the purity of the gas phase produced (reduction of separation cost). Research is underway in the form of co-catalysts of CO production catalyst like Au, Ag, Zn, Cu & H2 production catalysts. Because simply increasing the current density is not a good thing, but it must be able to maintain an industrially meaningful range of syngas ratios (1 to 3) while producing a high current density. Therefore, the potential window of studies on the rate-controlled syngas studied so far is typically high below -1.2V Vs RHE and high current density of ~ 30 mA/cm2. The reported lifetime at this level of current density is less than 10 hours, and for papers that report longer lifespans of tens to 100 hours, measured at 1 to 2 mA/cm2 levels. We fabricated Ag nanoparticle embedded in Zn dispersed carbon nanofiber to maintain syngas ratio stably in high potential window. In this catalyst carbon nanofiber produces H2 and Ag produces CO and dispersed Zn helps Ag in high potential.We annealed electrospun PAN/zinc nitrate&silver nitrate nanofiber at 800°C 3h in N2 ambient after stabilization in air. From this, we obtained Ag nanoparticle embedded in Zn & N doped carbon nanofiber. Ag tends to form nanoparticle and non-particle Zn was dispersed in carbon nanofiber. we obtained almost potential insensitive syngas ratio unlike conventional Ag catalyst in syngas production. Only N-doped carbon nanofiber sample produced increasing H2 with potential. Zn & N doped carbon nanofiber produced ratio of syngas higher than 2. Ag nanoparticle embedded carbon nanofiber produced ratio of syngas lower than 1 and sharply increased in higher potential (< -1.6V Vs. RHE). However, Ag nanoparticle embedded in Zn & N-doped carbon nanofiber maintained its low ratio of around 0.5 even in -2.2 V Vs. RHE and almost potential insensitive. We altered this insensitive syngas ratio with the mass ratio between carbon nanofiber and Ag/Zn-carbon nanofiber. It made syngas ratio increases slowly with potential and overall syngas ratio can be shifted with the mass of carbon nanofiber.

Fe1-xS Modified TiO2 NPs Embedded Carbon Nanofiber Composite via Electrospinning: A Potential Electrode Material for Supercapacitors.

Fe1−xS-TiO2 nanoparticles embedded carbon nanofibers (Fe1−xS-TiO2/CNFs) composite as a supercapacitor electrode material has been reported in the present work. The Fe1−xS-TiO2/CNFs composite was fabricated by electrospinning technique followed by carbonization under argon atmosphere and characterized by the state-of-art techniques. The electrochemical studies were carried out in a 2 M KOH electrolyte solution. The synthesized material showed a specific capacitance value of 138 F/g at the current density of 1 A/g. Further, the capacitance retention was about 83%. The obtained results indicate that the Fe1−xS-TiO2/CNFs composite can be recognized as electrode material in supercapacitor.

MoC nanoparticle-embedded carbon nanofiber aerogels as flow-through electrodes for highly efficient pseudocapacitive deionization

Highly efficient pseudo-capacitive deionization systems equipped with flow-through electrodes are developed for the first time based on the utilization of MoC nanoparticle-embedded carbon nanofiber aerogels as electrode materials.

Cr3C2 Nanoparticle-Embedded Carbon Nanofiber for Artificial Synthesis of NH3 through N2 Fixation under Ambient Conditions.

Industrial production of NH3 heavily depends on the conventional Haber-Bosch process under rigorous conditions with a large amount of energy consumption and carbon emissions. Electrocatalysis exhibits an intriguing prospect for the N2 reduction reaction (NRR) at ambient conditions. In this case, a high-efficiency and low-cost catalyst is paramount. In this letter, Cr3C2 nanoparticles and carbon nanofiber composite (Cr3C2@CNF) are proposed as a noble-metal-free NRR electrocatalyst for converting N2 to NH3 with an excellent selectivity. The optimal Faradic efficiency and NH3 yield rate achieved are as high as 8.6% and 23.9 μg h-1 mgcat.-1 at -0.3 V vs reversible hydrogen electrode in 0.1 M HCl, respectively. Theoretical calculations show a low reaction barrier of merely 0.53 eV in the enzymatic route for this catalyst.

Bismuth oxide nanoparticles embedded carbon nanofibers as self-standing anode material for Na-ion batteries

Graphite, the most commonly used anode material for lithium-ion batteries (LIBs), cannot be employed for sodium-ion batteries (SIBs) with conventional carbonate-based electrolyte since the interlayer spacing of graphite is not large enough for sodium ions to be de/intercalated. Bismuth oxide (Bi2O3) is considered as suitable alternative anode material for SIBs owing to its good theoretical specific capacity. However, the volume expansion taking place during discharge and low electrical conductivity result in poor cycling performance and fast capacity fading. Thus, composites with carbon materials are usually preferred to overcome those issues. In this work, Bi2O3 nanoparticles were incorporated in carbon nanofibers (CNF) via electrospinning method. The CNF-Bi2O3 self-standing nanocomposite anode material exhibited excellent rate capability (i.e. 504 mAh g−1 after 100 cycles at 25 mA g−1 current density) and superior capacity values (393 mAh g−1 at 625 mA g−1).

Palladium on yttrium-embedded carbon nanofibers as electrocatalyst for oxygen reduction reaction in acidic media

Pd-Y alloy nanoparticle-embedded carbon nanofiber (CNF) were sequentially synthesized by electrospinning a solution mixture containing Y precursor and polyacrylonitrile, stabilization, carbonization at 1200 °C, activation, and impregnation of Pd. The CNF acted as catalytic supports and templates, retaining the nanoparticle size at high temperatures; under these conditions, other nanomaterials would easily aggregate or sinter. To expose the surface of Y nanoparticles embedded into the CNF (Y-ACNF), mild and selective oxidation was conducted. The impregnated Pd exhibited the excellent degree of alloying with and dispersion on Y-ACNF, leading to outstanding activity with four-electron reaction of Pd3/Y-ACNF for oxygen reduction reaction comparable to commercial platinum-based catalysts.

ZrO2 nanoparticle embedded carbon nanofibers by electrospinning technique as advanced negative electrode materials for vanadium redox flow battery

ZrO2 nanoparticle decorated carbon nanofibers (ZrO2/CNF) were explored by electrospinning technique with ZrOCl2·8H2O and polyacrilonitrile (PAN) as precursors, and were considered as negative electrode for vanadium redox flow battery (VRFB). It is found that the ZrO2 nanoparticle uniformly embedded in the CNF not only increases the disorder of CNF, but also improves the catalytic activity of CNF, further resulting in good electrochemical activity. Specially, the sample with proper content of ZrO2 (CNFZrO2-18) shows superior electrochemical activity for the negative couple for VRFB. Furthermore, the charge-discharge tests verify that CNFZrO2-18 can enhance performance of cell. At 100 mA cm−2, the discharge capacity and energy efficiency of the cell with CNFZrO2-18 arrive at 91.5 mA h and 73.3%, 8.7% and 8.3% more than those of pristine cell, respectively. After charging and discharging for 50 cycles at 80 mA cm−2, the cell exhibits outstanding stability with initial discharge capacity retention of 95.0%. The high electrochemical performance of ZrO2/CNF mainly comes from the good electrocatalytic properties of ZrO2 and in situ decoration for CNF by electrospinning technique.

Fabrication and Characterizations of Silica Nanoparticle Embedded Carbon Nanofibers

Silica nanoparticle/carbon nanofiber composites were fabricated via electrospinning of the apolymeric precursor solution (polyacrylonitrile polymer in N,N-dimethylformamide solvent) containing silica nanoparticles followed by carbonization in an inert gas. The properties of surface morphology, surface area, surface chemistry, and mechanical strength were characterized using Fourier transform scanning electron microscopy (SEM), N2 physisorption analyzer, infrared spectroscopy (FTIR), and dynamic mechanical analyzer (DMA). SiO2 nanoparticles with average size about 200 nm exhibited dispersion along the carbon nanofiber surface. Here, the capability to use silica nanoparticles was demonstrated to create high-surface-area carbonized nanofiber with improved mechanical strength for easier handling in the applications requiring good mechanical properties materials such as water treatment processes. The specific surface area of the PAN/silica carbon nanofiber composite reached 280 m2/, which is higher than the su...

FeCo nanoparticles-embedded carbon nanofibers as robust peroxidase mimics for sensitive colorimetric detection of l-cysteine.

A simple and low cost detection of l-cysteine is essential in the fields of biosensors and medical diagnosis. In this study, we have developed a simple electrospinning, followed by calcination process to prepare FeCo nanoparticles embedded in carbon nanofibers (FeCo-CNFs) as an efficient peroxidase-like mimic for the detection of l-cysteine. FeCo nanoparticles are uniformly dispersed within CNFs, and their diameters are highly influenced by the calcination temperature. The calcination temperature also influences the peroxidase-like catalytic activity, and the maximum activity is achieved at a calcination temperature of 550 °C. Owing to the high catalytic activity of the as-prepared FeCo-CNFs, a colorimetric technique for the rapid and accurate determination of l-cysteine has been developed. The detection limit is about 0.15 μM with a wide linear range from 1 to 20 μM. In addition, a high selectivity for the detection of l-cysteine over other amino acids, glucose and common ions is achieved. This study provides a simple, rapid and sensitive sensing platform for the detection of l-cysteine, which is a promising candidate for potential applications in biosensing, medicine, environmental monitoring.

Ultrasmall titanium oxide/titanium oxynitride composite nanoparticle-embedded carbon nanofiber mats as high-capacity and free-standing electrodes for lithium sulfur batteries

TiO2/TiOxNynanoparticles loaded CNFs have been synthesized as free-standing electrodes for high performance lithium–sulfur batteries, showing high reversible capacity of 1107 mA h g−1after 100 cycles at 1C with superior capacity retention of 85%.

Reduction of Charge and Discharge Polarization By Cobalt Nanoparticles-Embedded Carbon Nanofibers for Lithium-Oxygen Batteries

The battery material community has a persistent consensus that Li–O2 batteries would be the most promising next generation batteries due to its extraordinarily high energy densities; from a practical view point, at least 2~3 times higher than those of conventional lithium ion batteries (LIBs).[1] However, Li–O2 batteries suffer from their chronically low round trip efficiency due to poor reversibility of lithium peroxide, Li2O2, which is main product of discharged Li–O2 batteries. This truly originates from its intrinsically poor electron and ionic conductivity.[2] Therefore, the reduction of charging overpotential is in urgent need for economical progress of Li–O2 batteries. In an effort to achieve high round trip efficiency, recent studies have attracted great attention that the charge behaviors of Li–O2 cells can be manipulated by controlling the phase structure and morphology of Li2O2 formed during discharge. In particular, at a low current density, the large toroidal structured, crystalline Li2O2 was primarily formed. In contrast, the formation of film-like amorphous Li2O2 is favored at high current density. [3,4] Owing to its structural advantages of enhanced ionic and electronic transport[5], the oxidation of less crystalline Li2O2 is more efficient, resulting in significant decrease on charge overpotential. Consequently, the controlling phase and morphology of Li2O2 is an effective strategy for manipulating charge behavior of Li–O2 cells. As a possible approach for controlling Li2O2, we designed an effective electrochemical catalyst of oxygen reduction reactions in Li-O2 batteries, a cobalt nanoparticles (Co NPs) embedded carbon nanofibers (Co-CNFs). As a result, embedded Co NPs leads to the formation of uniform film-like amorphous Li2O2, and thus, the Li–O2 battery employing the Co-CNF provides a round trip efficiency of > 77% and extends cycling stability by more than 6 times in comparison with a CNF electrode. These change of Li2O2 mainly is derived from a charge delocalization originating from the electron transfer from Co NPs to C-atoms. According to HSAB theory, highly concentrated Li+ ions near electrode resulting from the preferable interaction with Co-CNFs could lead to the rapid precipitation of Li2O2 and prevent the crystallization of Li2O2. The findings suggest a novel electrode design strategy of combining inexpensive metal and carbons for modulating the phase of discharge product.

A novel nonenzymatic hydrogen peroxide sensor based on electrospun nitrogen-doped carbon nanoparticles-embedded carbon nanofibers film

A novel nonenzymatic electrochemical sensor for the detection of hydrogen peroxide (H2O2) was developed based on free-standing nitrogen-doped carbon nanoparticles-embedded carbon nanofibers (NCNPFs) film, which were prepared by the carbonization of electrospun polypyrrole nanoparticles/polyacrylonitrile (PPy NPs/PAN) composite nanofibers. A series of NCNPFs-x samples with different mass concentration of PPy NPs to PAN (wt.%) were prepared. When the PPy NPs precursor is 12wt.%, large amount of resulting NCNPs are embedded uniformly in NCNFs substrate without obvious aggregation. The as-obtained NCNPFs-12wt.% has smaller diameter, higher content of pyrrolic-N and more defective sites, which result in high electrocatalytic activity for H2O2 reduction. The NCNPFs-12wt.%-based H2O2 sensor shows a fast amperometric response within 2s, and a wide linear range of 5.0×10−6 to 2.7×10−2M with a high sensitivity of 383.9μAμM−1cm−2. In addition, this nonenzymatic sensor displays good selectivity, high reproducibility and long-term stability. Because of the remarkable analytical performances, the NCNPFs-12wt.%-based electrochemical sensor shows potential applications for the detection of H2O2 in human serum and disinfectant samples with satisfactory results.

High Formic Acid Oxidation Activity and Stability of Pd Catalyst Supported by Nanoparticle-Embedded Carbon Nanofiber

A nanoparticle-embedded carbon nanofiber (PECNF) was proposed as a promising support of the Pd nanoparticle catalyst for formic acid oxidation reaction (FAOR). The nanofiber supports contained different weight and different nanoparticle were prepared by the electrospinning of polyacrylonitrile (PAN) by adding the nanoparticles, TiO2: TECNF, SiO2: SECNF and carbon black: CECNF, followed by carbonization and steam activation of the nanofiber. Cyclic voltammetry (CV) revealed a significantly high FAOR activity for the Pd/SECNF [1.00], which showed “muskmelon” like structure. Moreover, the chronoamperometory (CA) revealed a higher durability of the Pd/PECNF than that of Pd/CNF. Especially, Pd/SECNF [0.50] showed excellent durability. Based on these results, it was found that the SECNF is a promising support of the Pd for the DFAFC anode.

Reduction of Charge and Discharge Polarization by Cobalt Nanoparticles-Embedded Carbon Nanofibers for Li-O2Batteries

Invited for this month’s cover is the group of Jung-Ki Park and Hee-Tak Kim at Korea Advanced Institute of Science and Technology. The image shows cobalt nanoparticles embedded in carbon nanofibers for use in lithium oxygen (Li–O2) battery: the fibers attract oxygen molecules and lithium ions due to a charge transfer from cobalt nanoparticles to carbon, inducing the formation of amorphous lithium peroxide. The Full Paper itself is available at 10.1002/cssc.201500520.

Reduction of charge and discharge polarization by cobalt nanoparticles-embedded carbon nanofibers for Li-O2 batteries.

The problem of high charge polarization is one of the most significant challenges in current nonaqueous Li-O2 batteries. The development of an electrode for the oxygen evolution reaction (OER) at reduced overpotential is thus essential. Here, we suggest a binder-free electrode based on Co nanoparticles embedded in carbon nanofibers (Co-CNFs), which simultaneously reduces the charge and discharge polarization and extends cycling stability. Co-CNF gives rise to a lower discharge polarization because of an enhanced oxygen reduction reaction activity compared to Co-free CNF. Although the embedment of Co does not enhance the OER activity, it significantly reduces charge overvoltage by forming easily decomposable amorphous Li2 O2 . A mechanism for the formation of amorphous Li2 O2 is suggested in terms of charge localization induced by the Co NPs. The findings suggest a new electrode design strategy of combining inexpensive metals and carbon materials for modulating the phase of the discharge product.

High Formic Acid Oxidation Activity and Stability of Pd Catalyst Supported by Nanoparticle-Embedded Carbon Nanofiber

1. Introduction Direct formic acid fuel cells, DFAFCs, have attracted as the alternative electric power source for the hydrogen fuel cells with a polymer electrolyte, PEFCs, due to the easy handling of the liquid fuel and the low operating temperatures. However, the power density of the DFAFCs are half or a forth comparing to that of PEFCs. Therefore, the enhancement of the catalyst activity is required in order to improve the power density of DFAFC. Ito et.al reported that PtRu nanoparticles supported on TiO2-embedded carbon nanofibers, PtRu/TECNF, showed a grate methanol electro- oxidation activity [1]. In this study, nanoparticle- embedded carbon nanofibers, PECNF, were proposed as a promising support of the Pd catalyst for the formic acid oxidation reaction. We prepared the PECNFs which contained three different nanoparticles (TiO2, SiO2, Vulcan XC-72R) as a support of the Pd catalyst and compared the formic acid oxidation reaction (FAOR) activities. 2. Experiment The nanofiber supports were prepared by the electrospinning of polyacrylonitrile (PAN) with nanoparticles followed by carbonization and steam activation of nanofiber as same as previous report [1]. The TiO2-emmbedded carbon nanofiber, SiO2-emmbedded carbon nanofiber and Vulcan carbon-emmbedded carbon nanofiber were denoted TECNF, SECNF and CECNF, respectively. 20 wt% of Pd nanoparticles were deposited on the prepared supports by the reduction of the Pd Cl2. The FAOR activities of the prepared catalysts were evaluated by the cyclic voltammetry, CV, in a three-electrode cell with a fixed glassy carbon electrode (GCE) (3-mm diameter) at room temperature. The electrolyte solution was a 3 M formic acid containing 0.5 M H2SO4. The CV measurements were conducted in the potential range from 0 to 1.2 V vs.NHE at the scan rate of 20 mV s-1 with N2 bubbling at room temperature. 3. Result and discussion Figure 1 shows the SEM images for the PECNFs obtained after steam activation. The surface of CNFs is flat, on the other hand, that of SECNFs is bumpy. We also confirmed that the surfaces of TECNF and CECNF were bumpy. The average diameter of fiber is approximately 300 nm in all the samples irrespective of with or without nanoparticles. Figure 2 shows the effect of the nanoparticles embedded in the CNF on the CV profile. For the comparisons, Pd/CNF and Pd/C were also shown in Fig.2. The highest FAOR activity of 3151 mA mg-Pd -1, which is 12.6 times higher than that of Pd/C, was obtained in the case of Pd/SECNF. Pd/TECNF and Pd/CECNF also showed higher FAOR activity, 618 mA mg-Pd and 1010 mA mg-Pd, respectively, than that of Pd/C. On the other hand, Pd/CNF showed lower FAOR activity than that of Pd/C. Therefore, it is found that the fiber structure was not contributed to the high FAOR activity. It has been reported that SiO2 and TiO2 showed strong metal-support interaction. Due to this, SECNF and TECNF showed higher FAOR activity. In case of CECNF, Vulcan contained in the CNF was carbonized and activated by steam with CNF. There is a possibility that Vulcan embedded in the CNF showed stronger metal-support than the Vulcan used in Pd/C by doing these treatments. Moreover, it is considered that the high activity of the PECNF is influenced by not only metal-support interaction but also the electrical conductivity. Based on these results, it was confirmed that the PECNF is the promissing support of the Pd for the FAOR. The highest catalyst activity was obtained using Pd/SECNF. This might be mainly attributed to the metal-support interaction between SiO2 and Pd 4. Conclusion Using PECNF, the FAOR activity was enhanced irrespective of the nanoparticles. Pd/SECNF showed the highest FAOR activity comparing to that of the other catalysts prepared in this study. Acknowledgement This work was supported by JST, PRESTO. Reference [1] Y.Ito et al,J.Power Sources 242(2013)280-288. Figure 1