KR101479636B1 - Nanocomposite catalyst for fuel cell and its preparing method - Google Patents

Abstract

The present invention relates to a nanocomposite catalyst for polymer electrolyte membrane fuel cells (PEMFCs).
According to the present invention, a metal catalyst material is supported on a graphene nano-monolayer to block re-deposition of a graphene nano single sheet (GNS), and carbon black (CB) is introduced By providing a nanocomposite catalyst and a method for producing the nanocomposite catalyst, the specific surface area of the graphene mono single layer film can be maintained at a very high level, and a polymer electrolyte fuel cell exhibiting excellent performance can be manufactured.

Description

TECHNICAL FIELD [0001] The present invention relates to a nanocomposite catalyst for a fuel cell,

The present invention relates to a nanocomposite catalyst for polymer electrolyte membrane fuel cells (PEMFCs), and more particularly to a nanocomposite catalyst for graphene nano single sheet (GNS) To a nanocomposite catalyst in which a metal catalyst material is supported on a monolayer film and carbon black (CB) is introduced, and a method for producing the same.

Future energy issues will require a shift from fossil fuels to more environmentally friendly and more sustainable energy sources. As an alternative energy source, polymer electrolyte membrane fuel cells (PEMFCs) are attracting much attention as energy-related energy technologies for power supply and fixed power supply for transportation vehicles, small portable electronic devices. Despite significant development of PEMFC technology, catalyst stability and durability should still be improved. In particular, carbon-based electrochemical catalysts are an important factor in upgrading the performance of PEMFCs and carbon black (CB) is currently the most widely used support, but under severe operating conditions there is a serious self-sufficiency phenomenon.

As alternative carbon materials, carbon nanotubes (CNTs) have attracted much attention as alternative carbon materials because of their unique structural / electrical properties. Another interesting alternative, carbon molecular sieve (CMS), has attracted attention because of its outstanding surface properties, relatively uniform sieve pore size, and noticeable properties such as ordered body structures. However, many researchers have been actively studying graphene in the last few years after the existence of two-dimensional graphene has been known. The electrochemical performance of a single graphene nano single sheet (GNS) has been reported to be superior to that of graphene oxide (GO). In terms of methanol oxidation performance, Pt / It has been reported that it is better than the XC-72 carbon molecular sieve.

However, the possibility of PT / GNS in battery performance has been limited so far.

Despite the excellent electrical conductivity of graphene, each single graphene nanotomes (GNS) is re-deposited, and when it is re-deposited, one side becomes unusable and the Pt active site is reduced and used as an effective carbon support It became a disorder. To overcome this problem, it is possible to add an additional Nafion ionomer, but adding too much ionomer can cause the electrode to become thicker, increasing the mass transfer resistance and reducing the conductivity of the electrode.

On the other hand, another method is to introduce carbon black (CB) between single graphene mono-layer films (GNS). An advantage of the method of introducing carbon black (CB) is that the single graphene mono-layer films (GNS) are not re-deposited, so that not only the mass transfer but also the fuel can improve the accessibility to the Pt active site. Thus, the present inventors have made an effort and an effort to accomplish the present invention.

On the other hand, Korean Patent Publication No. 10-2011-0051584 (a method for producing graphene using a catalyst alloy) and Korean Patent No. 10-1148844 (method for producing graphene using a metal catalyst) However, the present invention does not disclose the invention in which carbon black (CB) is introduced between single graphene mono-layer films (GNS) to prevent the graphene mono-layer films (GNS) from being re-deposited.

In order to prevent re-deposition of a graphene nano single sheet (GNS), the present inventors have developed a graphene nano single sheet (GNS) by carrying a metal catalyst material on a graphene mono-layer film and then introducing carbon black It has been experimentally confirmed that the specific surface area of the monolayer membrane can be maintained at a very high level, and that the performance of the polymer electrolyte fuel cell including such a nanocomposite catalyst is improved, thereby completing the present invention.

It is an object of the present invention to provide a nanocomposite catalyst for a fuel cell in which a carbon black (CB) is introduced into a graphene nano single sheet (GNS) carrying a metal catalyst material, And to provide a fuel cell including an electrode.

Another object of the present invention is to provide a method for producing a nanocomposite catalyst for a fuel cell wherein carbon black (CB) is introduced into a graphene nano single sheet (GNS) carrying a metal catalyst material have.

In order to achieve the above object, the present invention provides a nanocomposite catalyst for a polymer electrolyte fuel cell, wherein carbon black (CB) is introduced into a graphene nano single sheet (GNS) carrying a metal catalyst material Thereby providing a nanocomposite catalyst for a fuel cell.

Wherein the metal catalyst material comprises at least one metal selected from the group consisting of Pt, Pd, Ag, Cu, Ni, Co, Mo, Ru, Re, Rb, Pb and La and a metal oxide comprising the metal And at least one selected from the above. However, it is preferable to select Pt having an average particle size of 2 to 5 nm. Meanwhile, the thickness of the graphene nano single sheet (GNS) is preferably 0.3 to 0.4 nm.

The carbon black (CB) is contained in an amount of 1 wt% to 30 wt%.

The present invention also provides a fuel cell including an electrode including the nanocomposite catalyst.

(1) preparing a graphene nano single sheet (GNS), and (2) supporting a metal catalyst material on the GNS prepared by the step (1). And (3) introducing carbon black (CB) into the metal / GNS prepared in the step (2).

In the step (1), the graphene nano single sheet (GNS) is obtained by a) oxidizing the graphite powder and b) oxidizing the graphite powder oxidized by the pre- To produce graphene oxide (GO); And c) placing the graphene oxide (GO) in a heating furnace and thermally peeling the graphene oxide (GO).

The metal catalyst material may be at least one metal selected from the group consisting of Pt, Pd, Ag, Cu, Ni, Co, Mo, Ru, Re, Rb, Pb and La, And an oxide of at least one selected from the group consisting of. However, it is preferable to select Pt having an average particle size of 2 to 5 nm. Meanwhile, the thickness of the graphene nano single sheet (GNS) is preferably 0.3 to 0.4 nm.

In step (3), carbon black (CB) is contained in an amount of 1 wt% to 30 wt%.

The present invention also provides a nanocomposite catalyst for a fuel cell manufactured by a manufacturing method.

According to the present invention, a metal catalyst material is supported on a graphene nano-monolayer to block re-deposition of a graphene nano single sheet (GNS), and carbon black (CB) is introduced By providing a nanocomposite catalyst and a method for producing the nanocomposite catalyst, the specific surface area of the graphene mono single layer film can be maintained at a very high level, and a polymer electrolyte fuel cell exhibiting excellent performance can be manufactured.

1 is a graph showing an XRD pattern of graphite, graphene oxide (GO), and graphene single nanosheet (GNS).
2 is a SEM image of a) graphite, b) graphene oxide (GO), and c) a graphene single nanosheet (GNS).
3 is a graph showing the XRD pattern of a) Pt / GNS, b) commercial Pt / Vulcan XC-72CB, and c) Pt / CB.
Figure 4 is an AFM image for measuring the thickness of a graphene single nanosheet (GNS).
5 is a graph showing TG / DTA curves of (/,) Pt / GNS and (·, O) graphene oxide (GO).
6 is a graph showing a pore size distribution of a nitrogen (N ₂ ) adsorption isotherm and a graphene single nanosheet (GNS) according to the present invention.
7 is a FT-IR spectrum graph of a) graphite, b) graphene oxide (GO), and c) graphene single nanosheet (GNS).
Figure 8 shows a) TEM image of Pt / GNS. b) Particle size distribution graph.
Figure 9 is an XPS spectrum graph of a) graphite, b) graphene oxide (GO), and c) graphene single nanosheet (GNS).
10 is a graph showing CV values of Pt / GNS, commercial Pt / Vulcan XC-72CB and Pt / CB for ECSA.
11 is a graph showing cell polarization curves of Pt / GNS, Pt / GNS / CB20, Pt / GNS / CB30 and Pt / GNS / CB40.
12 is a graph showing CV values of Pt / GNS / CB20, Pt / GNS / CB30 and Pt / GNS / CB40 for ECSA.

The present invention relates to a nanocomposite catalyst for a polymer electrolyte fuel cell, which comprises a nanocomposite catalyst for a fuel cell in which carbon black (CB) is introduced into a graphene nano single sheet (GNS) carrying a metal catalyst material to provide. Wherein the metal catalyst material comprises at least one metal selected from the group consisting of Pt, Pd, Ag, Cu, Ni, Co, Mo, Ru, Re, Rb, Pb and La and a metal oxide comprising the metal And at least one selected from the above. However, it is preferable to select Pt having an average particle size of 2 to 5 nm. Meanwhile, the thickness of the graphene nano single sheet (GNS) is preferably 0.3 to 0.4 nm. Also, carbon black (CB), which is introduced for re-layering the graphene mono-layer film on which the metal catalyst material is supported, is preferably contained in an amount of 1 wt% to 30 wt%. When the carbon black (CB) is contained in an amount of 30 wt.% Or more, the performance of the fuel cell deteriorates.

Hereinafter, the present invention will be described in more detail with reference to Examples. It is to be understood by those skilled in the art that these embodiments are merely illustrative of the present invention and that the scope of the present invention is not construed as being limited by these embodiments.

Example 1. Synthesis of graphene single nanosheet (GNS)

GNS was synthesized by an easy method including chemical oxidation of graphite and thermal peeling. Graphene oxide (GO), an intermediate between graphite and GNS, was synthesized by modifying the Hummers method. The synthesis process will be described in detail as follows.

(1) To a mixture (Aldrich) obtained by adding 2.5 g of K ₂ S ₂ O ₈ and 2.5 g of P ₂ O ₅ to 50 ml of concentrated sulfuric acid (H ₂ SO ₄ ), ₂ g of graphite powder was added. After mixing for 2 hours at 80 ° C, the mixture was cooled to room temperature for 6 hours, diluted with 0.5 L of distilled water, and then dried at room temperature overnight.

(2) The graphite powder subjected to the oxidation treatment by the pretreatment was placed in 35 ml of concentrated sulfuric acid (0 ° C), and 6 g of KMnO ₄ (Aldrich) was slowly added thereto. At this time, the temperature of the mixture was maintained at 20 ° C or lower in an ice bath. Then, the mixture was stirred at 35 ° C for 30 minutes, diluted by adding 100 ml of distilled water, stirred at 95 ° C for 30 minutes, and then 150 ml of distilled water and 10 ml of 30 wt% The reaction was terminated. About 15 minutes later the color of the mixture became bright yellow with bubbles.

(3) The mixture was filtered through filter paper, and 100 ml of 10 wt.% HCl was added to remove the metal ion. 500 ml of distilled water was added to remove the acid component. Then, GO powder was obtained by high-speed centrifugation and drying in a vacuum oven at 60 DEG C for 12 hours. The GO powder was put into a tubular furnace and subjected to reduction by thermal exfoliation by exposure to Ar for 30 seconds at a temperature of 1000 ° C. As a result, a graphene single nanosheet (GNS) was obtained.

Example 2. Preparation of GNS-based Pt nanoparticle catalyst

20 ml of distilled water containing 20 mg of the GNS powder prepared in Example 1 was ultrasonicated for 1 hour to prepare a GNS suspension solution. Then, 40 ml of ethylene glycol and 1 ml of a 0.02 mol Pt precursor (aqueous solution of H ₂ PtCl ₆ .6H ₂ O) were added to the suspension solution and stirred for 1 hour. Thereafter, the solution was stirred and heated to 100 DEG C by an oil bath and maintained for 24 hours. And centrifuged to separate Pt / GNS from ethylene glycol and washed five times with deionized water. Meanwhile, the finally prepared Pt / GNS was vacuum-dried at 60 DEG C for 12 hours.

Example 3. Preparation of Pt / GNS with carbon black (CB)

To introduce carbon black (CB) between the Pt / GNS prepared in Example 2, CB of 20 wt.%, 30 wt.%, 40 wt.% Was added to 24 mg of Pt / GNS, To the mixture was added 85 mg of 5 wt.% Nafion ^TM dispersion medium (Dupont Chem. CO.) And 1 mL of IPA (99.5 wt.%, Samchun Chemicals) and sonicated at 50 ° C for 1 hour.

On the other hand, physical properties and electrochemical characteristics of the result obtained in Example 3 were measured through the following experiment.

Experimental Example 1. Measurement of physical properties

(1) XRD pattern identification and SEM analysis

Powder X-ray diffraction analysis (XRD, Rigaku Model D / Max 2200) using Cu K? Radiation was performed to obtain an XRD pattern. At 40kV 30mA, the scan speed was 5 ° min ^-1 and the resolution was 0.04 ° per 2θ.

As a result, the XRD pattern of the graphene single nanosheet (GNS) fabricated in Example 3 shows a progressive state change from graphite to GNS as shown in FIG. After the chemical oxidation, the C peak at 2θ 26.5 °, which is characteristic of the graphite, is changed to 2θ 12.3 °, and functional groups containing oxygen atoms such as epoxy functional group / carboxyl functional group / hydroxyl functional group are attached, To form a graphene oxide (GO). GNS was created by thermal exfoliation of the extended GO to the next step. The XRD pattern shows that the peak near 12.3 ° disappeared, which means that each layer of GO existing along the c-axis has been separated and the sp2 structure of carbon has been regenerated. The disappearance of the peak is because the regularly stacked structure has disappeared. In order to clarify this phase change, a scanning electron microscope (SEM, JEOL JSM-6308) analysis was performed and the results are shown in Fig. As can be seen in FIG. 2, it was confirmed that the graphite expanded to a layered structure through chemical oxidation.

As described in the experimental procedure described above, it was confirmed by XRD whether or not Pt particles were included in the GNS and included successfully. As can be seen from FIG. 3, in addition to the GNS-specific 24.5 ° peak, it corresponds to Pt (111) / Pt (200) / Pt (220) / Pt (311) at 2θ 40 ° / 46 ° / 67.5 ° / , The crystal structure of Pt is a face-centered cubic (fcc). The average size of the Pt particles was obtained from the Pt peak using the following Schrer equation.

[Equation 1]

Radians of Schrrer where L is the average particle size, 0.94 is a constant specific crystal structure (8 cube-shaped surface) constant, λ is the wavelength _kα (4.54056㎚) of X-ray, B is _2θ FWHM (full width at half maximum) when the Value, and [theta] _B is the angular position of the Pt (220) peak. When the FWHM value of Pt (220) was calculated and the Scherrer equation was calculated, the average size of the Pt particles attached to the GNS was 2.5 nm, 3.47 nm, and 3.50 nm, respectively.

On the other hand, AFM analysis was performed to determine whether the GNS was made and the thickness of the GNS was measured. The result is shown in FIG. The thickness of the GNS was about 0.35 nm.

(2) Thermogravimetric analysis (TGA)

Thermogravimetric analysis (TGA, Model TA2050 TA instruments) was performed to confirm the Pt content in Pt / GNS.

As a result, the Pt content of GNS was 42.9 wt.%. In case of GO, as shown in Fig. 5 (a), the water molecules contained were removed by raising the temperature to 100 ° C, about 5% of the total weight, and then the temperature was raised to 200 ° C, To decompose and remove unstable functional groups. At 530 ℃, complete reduction of GO was achieved. In contrast to GO, in GNS, weight reduction did not occur even when the temperature was increased to 200 ℃. This is because most of the functional groups containing oxygen atoms have already been removed in the process of being made.

(3) Measurement of N ₂ adsorption isotherm

The BNS (Brunauer-Emmett-Teller) surface area of the GNS was determined by measuring the adsorption of nitrogen while increasing the relative pressure from 0.01 to 0.05 at 77 K (Micrometrics, Tristar ™ II 3020).

The results are shown in FIG. 6 and there is a pronounced hysteresis, which appears to be due to the corrugated structure of the GNS. The BET surface area was measured to be about 388 m < ² > g < ^{-1 &} gt ;, and the Pt nanoparticles were found to be wide enough to spread. However, the measured surface area is smaller than the theoretical value because the GNS is re-deposited due to van der Waals force.

(4) FT-IR spectrum analysis

Fourier transform infrared spectroscopy (FT-IR) was used to confirm the presence of functional groups containing oxygen atoms.

The result is shown in FIG. The oxidation of the graphite, the GO is kind to the functional group, with the hydroxyl groups of the vibration of the water molecules, or adsorbed water molecules movement 3400cm ^-1, carbonyl / carboxyl groups 1727cm ^-1, 1625cm ^-1 aromatic groups, carboxyl groups 1384cm ^{- 1} , the epoxy group is 1261 cm ^-1 , and the alkoxy group is 1085 cm ^-1 . However, most of the functional groups are lost when they are reduced by thermal exfoliation.

(5) TEM analysis and particle size distribution analysis

The TEM image and particle size distribution of Pt / GNS are shown in FIG. The Pt nanoparticles on the GNS spread very uniformly, with an average size of 2.9 nm.

(6) XPS spectrum analysis

Finally, X-ray photoelectron spectroscopy (VG Multilab ESCA 2000) analysis was performed using Mg Kα radiation to confirm the oxidation state of the Pt nanoparticles and confirm formation of functional groups containing oxygen atoms on the surface of the obtained materials Respectively.

XPS analysis was performed to investigate the physical state of the graphite-derived material and investigate the oxidation state of Pt in the Pt / GNS. 9. Table 1 summarizes the results. As shown in Fig. 9 (a), (b) and (c), four different kinds of carbon were identified. The first is 284.4 eV for the sp2 bond, 285.3 eV for the second, 286.4 eV for the COC and 288.0 eV for the HO-C = O bond. The CC peak of graphite sharply decreases as it is oxidized as shown in Fig. 9. (a), and the oxygenated COC peak increases considerably as shown in Fig. 9. (b). On the other hand, when reduction by thermal exfoliation, the functional groups including oxygen atoms are considerably reduced as shown in Fig. 9. (c). Therefore, it can be evaluated by XPS data that GNS was successfully created. Figure 9 (d) shows the Pt 4f doublet of Pt nanoparticles based on GNS (4f _7/2 and 4f _5/2 ) XPS spectrum. The distribution of Pt (0) / Pt (2) / Pt (4) was seen in FIG. 9 (d). 4f _7/2 and 4f _5/2 peaks correspond to 71.1 eV and 74.3 eV, respectively, which are slightly lower than the standard binding energies of Pt (0) (71.4 eV and 74.5 eV). This is due to the electron transfer from the GNS to the Pt nanoparticles and the work function (4.48 eV) of the GNS is smaller than the work function of Pt (5.65 eV), so that the Pt / GNS hybrid structure is formed, Lt; RTI ID = 0.0 > electron transfer < / RTI > Table 2 summarizes the various oxidation states according to Pt species in Pt / GNS.

[Table 1]

[Table 2]

Experimental Example 2. Measurement of electrochemical characteristics

(1) Experimental method and experiment preparation

The ink slurry was prepared by sonicating a cathode ink slurry. The same amount of the ink slurry was dropped on a glass carbon electrode (GCE) with a micropipette to a size of 3 mm in area, 0.0706 cm ₂ , treated with a 1 μm Al ₂ O ₃ slurry, and used as a substrate for the carbon-based catalysis.

The cyclic voltammetry (CV) analysis was performed on a conventional triode electrochemical cell using GCE as the test electrode, Pt wire as the counter electrode, and a saturated calomel electrode (SCE) as the reference electrode. Electrochemical analysis was recorded as compared to a conventional hydrogen electrode (NHE). CV was measured using a potentiostat and a galvanostat at 25 ° C with 0.5 M sulfuric acid purged with nitrogen (IM6, Zahner). The voltage was varied between 0.05V and 1.20V in a triangular waveform at a rate of 50mVs- ¹ . In order to measure the electrochemical characteristics of the fuel cell electrode, a fuel cell performance test was performed.

(2) For the fuel cell test, the anode and the cathode were fabricated as follows. Catalyst inks were prepared for use with Pt / GNS and various contents of Pt / GNS / CB electrodes. A 5 wt.% Nafion ^TM dispersion medium (Dupont Chem. CO.) Was added to the Pt / GNS synthesized by the polyol method and isopropyl alcohol (IPA, 99.5 wt.%, Samchun Chemicals) was added as a solvent. To ensure thorough mixing, the catalyst ink was sonicated for 1 hour. Next, the catalyst ink was applied to a polymer electrolyte membrane (Nafion NRE-212, Dupont) at 3 × 3 cm 2 Lt; / RTI > ㎠ Pt was supported at an amount of about 0.2 mg to about 0.3 mg per 1 liter of the catalyst and used as an anode and a cathode. During the measurement, the temperature of the single cell was maintained at 80 ° C and hydrogen / oxygen gas saturated with water vapor was supplied to the anode as much as possible at 80 ° C.

As a second step of the experiment, other types of catalyst inks were prepared in the form of Pt / GNS / CBx with different contents of CB by 20 wt.%, 30 wt.%, And 40 wt.%. The next step is the same as described above. In all cases the addition of Nafion was maintained in the range of 0.25 mg to 0.3 mg.

(2) Experimental results

CV analysis for Pt / GNS was performed to confirm the electrochemically active surface area (ECSA) of Pt / GNS. For comparison, ECSA was measured for commercial Pt / Vulcan XC-72CB and Pt / CB (containing Pt in commercial CB in the laboratory). The resulting CV curve is shown in FIG. 10, the peaks between 0.0 V and 0.3 V correspond to peaks due to hydrogen adsorption / desorption, and the bilayer region between 0.3 V and 0.8 V is the region without hydrogen adsorbed, to be. For comparison, the ECSA value of Pt / GNS, including the case of commercial Pt / Vulcan XC-72CB and Pt / CB, is corrected based on the hydrogen adsorption / desorption charge value by the following equation and the bilayer charge- Respectively.

[Equation 2]

As a result, the value of Pt ECSA / GNS is 31.5m ² g ^-1, ECSA value of the commercial Pt / Vulcan XC-72CB ECSA is the value of 23.1m ² g ^-1, Pt / CB were in 22.5m ² g ^-1 Respectively.

Meanwhile, the cell performance of various MEAs composed of Pt / GNS / CB having different CB contents was measured, and the results are shown in FIG. 11. It can be seen from FIG. 11 that the cell performance is significantly improved as the CB content increases from 20 wt.% To 30 wt.%. It was concluded that CB was inserted between GNS to improve the utilization of Pt active site. It was certain to improve the power production capability over the entire current density. In other words, it shows improved activity at low current density and excellent mass transfer at high current density. However, when the amount exceeds 30 wt.%, The performance of the battery is rather reduced. If CB is excessive, it may be a reason to block the Pt active site and to resist mass transfer.

Finally, to investigate the ECSA of various Pt / GNS / CBx, CV curves were measured and the results are shown in FIG. According to the hydrogen desorption peaks, Pt / GNS, ECSA value of Pt / GNS / CB20, Pt / GNS / CB30, Pt / GNS / CB40 are each ^{31.5m 2 g -1, 28.6m 2 g} -1, 38.8m 2 g ^-1 , 30.4 m ² g ^-1 . Considering the results, it is concluded that low CB content in GNS is insufficient to operate as a good insert, while too high CB content blocks Pt active sites and reduces Pt utilization.

Experimental Example 3. Experimental Result

Summarizing the above experimental results, the present invention has successfully synthesized GNS from graphite using chemical oxidation and thermal delamination at 1000 < 0 > C. From the XRD pattern, it was found that GNS was formed from C (002) completely disappeared, and it was also confirmed through AFM image. The thickness of the GNS synthesized from the AFM image was found to be 0.35 nm. As confirmed by FT-IR, most of the functional groups containing oxygen atoms from the GNS were removed. The Pt particle size attached to the GNS was in good agreement with that measured by TEM at about 2.5 nm. The TEM images showed that the Pt nanoparticles were well dispersed on the GNS, and the XPS analysis showed that the amount of functional groups containing oxygen atoms in the GNS was drastically reduced after thermal exfoliation. The ECSA values measured by CV were highest in Pt / GNS, and were in the order of commercial Pt / Vulcan XC-72 CB and Pt / CB.

As a result of the battery test with Pt / GNS and various CB contents of Pt / GNS / CBx, it was found that solving the reclamation problem is crucial for Pt / GNS to be used in polymer electrolyte membrane fuel cell (PEMFC). When CB is included in Pt / GNS, the use of Pt is increased and the mass transfer of fuel to the Pt active site is facilitated, so that the performance of the PEMFC is remarkably improved. On the other hand, the amount of CB inserted into Pt / GNS was very important. If too much CB is inserted into the GNS, the Pt active point is rather concealed. The ECSA value of Pt / GNS / CB30 containing 30 wt.% Of CB was the maximum. In the case of MEAs made of Pt / GNS with the highest ECSA values, the cell performance is much lower than that of the MEAs made of Pt / GNS / CBx with CB inserted because the re-lamination phenomenon occurs seriously when compressed to form the MEA Because. This is because the reclamation layer causes serious resistance to the mass transfer of the fuel and reduces the use of Pt.

Having described specific portions of the present invention in detail, it will be apparent to those skilled in the art that this specific description is only a preferred embodiment and that the scope of the present invention is not limited thereby. It will be obvious. Accordingly, the actual scope of the present invention will be defined by the appended claims and their equivalents.

Claims (12)

In a nanocomposite catalyst for a polymer electrolyte fuel cell,
A nanocomposite catalyst for fuel cell, which incorporates carbon black (CB) into a graphene nano single sheet (GNS) carrying a metal catalyst material.
The method according to claim 1,
Wherein the metal catalyst material comprises at least one metal selected from the group consisting of Pt, Pd, Ag, Cu, Ni, Co, Mo, Ru, Re, Rb, Pb and La and a metal oxide comprising the metal Wherein the catalyst is at least one selected from the group consisting of a catalyst and a catalyst.
The method according to claim 1,
Wherein the carbon black (CB) is contained in an amount of 1 wt% to 30 wt%.
The method according to claim 1,
Wherein the thickness of the graphene nano single sheet (GNS) is 0.3 to 0.4 nm.
3. The method of claim 2,
Wherein the metal catalyst material is selected from Pt having an average particle size of 2 to 5 nm.
A fuel cell comprising an electrode comprising the nanocomposite catalyst of any one of claims 1 to 5.
(1) preparing a graphene nano single sheet (GNS);
(2) carrying a metal catalyst material on the GNS produced by the step (1);
(3) introducing carbon black (CB) into the metal / GNS prepared in the step (2).

[7] The method of claim 7, wherein the graphene nano single sheet (GNS)
a) oxidizing graphite powder;
b) secondary oxidation of graphite powder oxidized by pretreatment to produce graphene oxide (GO);
c) adding the graphene oxide (GO) to a heating furnace and thermally stripping the graphene oxide (GO).
8. The method of claim 7,
The metal catalyst material may be at least one metal selected from the group consisting of Pt, Pd, Ag, Cu, Ni, Co, Mo, Ru, Re, Rb, Pb and La, Wherein the catalyst is at least one selected from the group consisting of titanium oxide, titanium oxide, and titanium oxide.
8. The method of claim 7,
The method for producing a nanocomposite catalyst for a fuel cell according to claim 3, wherein the carbon black (CB) is contained in an amount of 1 wt% to 30 wt% in the step (3).
10. The method of claim 9,
Wherein Pt having an average particle size of 2 to 5 nm is selected as the metal catalyst material.











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