Preparation method and application of transition metal doped platinum-nickel intermetallic compound fuel cell catalyst

Abstract

The invention discloses a preparation method of a transition metal doped platinum-nickel intermetallic compound fuel cell catalyst, which comprises the following steps: (1) adding a platinum precursor, a nickel precursor, a transition metal precursor and carbon black into acetone, carrying out ultrasonic dispersion, and stirring at room temperature until the mixture is dried; (2) grinding the material obtained in the step (1) to be uniform, then carrying out heat treatment on the obtained powder under the heat treatment conditions that the temperature is increased to 700-900 DEG C from room temperature in an H2 / Ar atmosphere, and carrying out heat preservation for 2-4 hours; and after heat treatment, cooling to room temperature to obtain the transition metal doped platinum-nickel intermetallic compound fuel cell catalyst. Because the phase transformation temperature is low, the platinum-nickel intermetallic compound with the ordered structure is difficult to prepare by adopting a conventional heat treatment method. By introducing transition metal doping, the phase transition temperature is increased, and the problem is successfully solved; the synthesis raw materials are low in price and easy to obtain, the technological operation is simple and feasible, large-scale preparation is easy, and the application requirements of fuel cells are met.

Description

Technical Field

[0001] The present invention belongs to the technical field of preparation of fuel cell nano-catalysts, and particularly relates to a preparation method and application of a transition metal-doped platinum-nickel intermetallic compound fuel cell catalyst. Background Art

[0002] Proton exchange membrane fuel cells (PEMFCs) as an efficient and environmentally friendly energy conversion technology have attracted extensive attention. However, the slow kinetics of the cathode oxygen reduction reaction (ORR) and the large demand for expensive and scarce platinum (Pt)-based catalysts seriously hinder the large-scale commercialization process of PEMFCs.

[0003] Alloying platinum with inexpensive transition metals (M) such as iron, cobalt, nickel, copper, and zinc can reduce the content of platinum and enhance the ORR performance by decreasing the binding energy between platinum and oxygen-containing intermediates. Among Pt-based alloys, Pt 3 Ni and PtNi have received great attention as efficient catalysts for ORR. In particular, the (111) crystal plane of Pt 3 Ni has been identified as one of the most effective catalytic crystal planes for promoting ORR. However, under acidic and high-potential ORR reaction conditions, nickel in the PtNi alloy inevitably undergoes oxidation and dissolution, resulting in a rapid decline in ORR activity.

[0004] In PtM alloys prepared under normal conditions, Pt and the transition metal M are disordered, and M atoms are easily dissolved into the electrolyte. If the disordered solid solution alloy is transformed into an ordered intermetallic compound, the dissolution of the non-noble metal M can be significantly inhibited, and the stability and durability of the catalyst can be improved. Preparing intermetallic compounds usually requires high-temperature heat treatment to increase the atomic mobility and promote the ordered arrangement of atoms. However, if the heat treatment temperature exceeds the stable temperature of the intermetallic compound, it will become a disordered solid solution alloy again. That is, the ordered transformation of the alloy needs to occur below their respective phase transition temperatures. For platinum-based alloys with high phase transition temperatures, such as PtFe and PtCo, they can be prepared by a simple annealing method. For example, PtFe with a relatively high phase transition temperature (~1350 °C) can undergo an ordered transformation when heated to 800 °C. However, due to the relatively low phase transition temperatures of L1 0 type PtNi (~630 °C) and L1 2 type Pt 3 Ni (~490 °C), when the disordered platinum-nickel alloy is heat-treated below the phase transition temperature, the atomic diffusion rate is very slow, and it is difficult to obtain an ordered alloy, especially the highly active L1 2 type Pt 3 Ni intermetallic compound. Therefore, obtaining ordered L1 0 type PtNi and L1 2Type Pt 3 Ni still faces significant challenges.

[0005] Some preparation methods of platinum-nickel ordered intermetallic compounds have been proposed in the prior art. For example, CN105854897A discloses a preparation method of a high-loading platinum-nickel ordered intermetallic compound, and CN105903479A discloses a preparation method of a platinum-nickel intermetallic compound with a platinum-rich surface. However, the preparation processes of these technical solutions are time-consuming, and the obtained particle size is greater than 10 nanometers, with poor performance and not meeting the commercial performance standards. The disclosed preparation strategies for platinum-nickel ordered alloys mainly target L1 0 type PtNi, while the preparation method of L1 2 type Pt 3 Ni intermetallic compounds has not been disclosed. Summary of the Invention

[0006] The purpose of the present invention is to overcome the defects of the prior art and provide a preparation method of a fuel cell catalyst based on a transition metal-doped platinum-nickel intermetallic compound.

[0007] Another purpose of the present invention is to provide the application of the fuel cell catalyst based on the transition metal-doped platinum-nickel intermetallic compound prepared by the above preparation method.

[0008] The technical solution of the present invention is as follows:

[0009] A preparation method of a fuel cell catalyst based on a transition metal-doped platinum-nickel intermetallic compound, comprising the following steps:

[0010] (1) Add a platinum precursor, a nickel precursor, a transition metal precursor, and carbon black to acetone, and perform ultrasonic dispersion, and then stir at room temperature until dry;

[0011] (2) Grind the material obtained in step (1) until uniform, and then perform heat treatment on the obtained powder. The heat treatment conditions are: in an 8-12 vol% H 2 / Ar atmosphere, heat from room temperature to 700-900 °C, and keep warm for 2-4 h; after heat treatment, cool to room temperature to obtain the fuel cell catalyst based on the transition metal-doped platinum-nickel intermetallic compound, wherein the molar ratio of nickel to the transition metal is 6-9:1-4, and the molar ratio of nickel to platinum is 0.4-1:1.

[0012] In a preferred embodiment of the present invention, the transition metal is selected from titanium, vanadium, chromium, manganese, and iron.

[0013] More preferably, the transition metal precursor is selected from titanium acetylacetonate, vanadium acetylacetonate, chromium acetylacetonate, manganese acetylacetonate, iron acetylacetonate, titanium oxyphthalocyanine, vanadium oxyphthalocyanine, chromium phthalocyanine, manganese phthalocyanine, iron phthalocyanine, chromium nitrate, manganese nitrate, and iron nitrate.

[0014] In a preferred embodiment of the present invention, the platinum precursor is selected from platinum acetylacetonate, chloroplatinic acid, platinum nitrate, (1,5-cyclooctadiene)dimethylplatinum, dichloro(1,5-cyclooctadiene)platinum, trimethyl(methylcyclopentadienyl)platinum, potassium tetrachloroplatinate, potassium hexachloroplatinate, and platinum dichloride.

[0015] In a preferred embodiment of the present invention, the nickel precursor is selected from nickel acetylacetonate, nickel phthalocyanine, 2,3-naphthalocyanine nickel, nickel nitrate, and nickel chloride.

[0016] In a preferred embodiment of the present invention, the carbon black is selected from BP2000, ECP-600, ECP-300, and XC-72.

[0017] In a preferred embodiment of the present invention, the transition metal precursor is selected from titanium acetylacetonate, vanadium acetylacetonate, chromium acetylacetonate, manganese acetylacetonate, iron acetylacetonate, titanium oxophthalocyanine, vanadium oxophthalocyanine, chromium phthalocyanine, manganese phthalocyanine, iron phthalocyanine, chromium nitrate, manganese nitrate, and iron nitrate; the platinum precursor is selected from platinum acetylacetonate, chloroplatinic acid, platinum nitrate, (1,5-cyclooctadiene)dimethylplatinum, dichloro(1,5-cyclooctadiene)platinum, trimethyl(methylcyclopentadienyl)platinum, potassium tetrachloroplatinate, potassium hexachloroplatinate, and platinum dichloride; the nickel precursor is selected from nickel acetylacetonate, nickel phthalocyanine, 2,3-naphthalocyanine nickel, nickel nitrate, and nickel chloride; the carbon black is selected from BP2000, ECP-600, ECP-300, and XC-72.

[0018] More preferably, the platinum precursor is platinum acetylacetonate; the nickel precursor is nickel acetylacetonate; the transition metal precursor is selected from titanium acetylacetonate, vanadium acetylacetonate, chromium acetylacetonate, manganese acetylacetonate, and iron acetylacetonate; the carbon black is ECP-600.

[0019] Use of the transition metal-doped platinum-nickel intermetallic compound fuel cell catalyst prepared by the above preparation method in the preparation of fuel cells.

[0020] A fuel cell having the transition metal-doped platinum-nickel intermetallic compound fuel cell catalyst prepared by the above preparation method.

[0021] The beneficial effects of the present invention are:

[0022] 1. By introducing elements such as titanium, vanadium, chromium, manganese, and iron that can form L1 2 type intermetallic compounds with platinum (Pt), the present invention successfully prepares L1 2 type Pt 3 Ni intermetallic compounds. At the same time, by introducing vanadium, chromium, manganese, iron, etc. that can form L1 0Elements of the intermetallic compound of type L1 were successfully prepared. 0 type PtNi intermetallic compound, whose raw materials are inexpensive and easily accessible, the process operation is simple and feasible, and it is easy to prepare on a large scale, meeting the application requirements of fuel cells.

[0023] 2. The present invention adopts the impregnation method with simple industrial operation and successfully synthesizes a titanium-doped platinum-nickel intermetallic compound catalyst with an average particle size of 3 nm. The doping of transition metals effectively promotes the ordering of the platinum-nickel alloy, providing a new idea for the further commercial development of the oxygen reduction reaction at the cathode of fuel cells.

[0024] 3. Compared with the prior art, the transition metal-doped platinum-nickel intermetallic compound fuel cell catalyst prepared by the present invention has high oxygen reduction catalytic activity, making it excellent in terms of activity and stability as a catalyst, and showing good catalytic activity and application prospects in fuel cells. Description of the Drawings

[0025] Figure 1 X-ray diffraction patterns of Ti-Pt 3 Ni prepared in Example 1 of the present invention, Ti-Pt 3 Ni-1 prepared in Example 2 of the present invention, Ti-Pt 3 Ni-2 prepared in Example 3 of the present invention, Ti-Pt 3 Ni-3 prepared in Example 4 of the present invention.

[0026] Figure 2 High-angle annular dark-field scanning transmission electron microscope images of Ti-Pt 3 Ni-2 prepared in Example 3 of the present invention.

[0027] Figure 3 Scanning transmission electron microscope images and element distribution maps obtained by energy dispersive spectrometer testing of Ti-Pt 3 Ni-2 prepared in Example 3 of the present invention.

[0028] Figure 4 Transmission electron microscope images and particle size distribution maps of Ti-Pt 3 Ni-2 prepared in Example 3 of the present invention.

[0029] Figure 5 Transmission electron microscope images and particle size distribution maps of Pt 3 Ni prepared in Example 5 of the present invention.

[0030] Figure 6 Transmission electron microscope images of Ti-Pt 3 Ni prepared in Example 1 of the present invention, Pt 3 Ni prepared in Example 5 of the present invention, V-Pt 3Ni, Cr-Pt prepared in Example 7 3 Ni, Mn-Pt prepared in Example 8 3 Ni and Fe-Pt prepared in Example 9 3 X-ray diffraction pattern of Ni.

[0031] Figure 7 X-ray diffraction patterns of Ti-PtNi prepared in Example 10, PtNi prepared in Example 11, V-PtNi prepared in Example 12, Cr-PtNi prepared in Example 13, Mn-PtNi prepared in Example 14, and Fe-PtNi prepared in Example 15 of the present invention.

[0032] Figure 8 For Comparative Example 1, Ti-Pt prepared in Example 1 of the present invention 3 Ni, Pt prepared in Example 5 3 Ni, V-Pt prepared in Example 6 3 Ni, Cr-Pt prepared in Example 7 3 Ni, Mn-Pt prepared in Example 8 3 Ni and Fe-Pt prepared in Example 9 3 Ni in 0.1 mol / L HClO 4 ORR polarization curve of the solution.

[0033] Figure 9 For Ti-Pt prepared in Example 3 3 Linear sweep curves (left) of Ni-2 before and after 30,000 cycles of durability test, and comparison charts of mass specific activity and area specific activity (right).

[0034] Figure 10 For Pt prepared in Example 5 of the present invention 3 Linear sweep curves (left) of Ni before and after 30,000 cycles of durability test, and comparison charts of mass specific activity and area specific activity (right).

[0035] Figure 11 Linear sweep curves (left) of the catalyst prepared in Comparative Example 1 of the present invention before and after 30,000 cycles of durability test, and comparison charts of mass specific activity and area specific activity (right).

[0036] Figure 12 For Comparative Example 1, Ti-PtNi prepared in Example 10, PtNi prepared in Example 11, V-PtNi prepared in Example 12, Cr-PtNi prepared in Example 13, Mn-PtNi prepared in Example 14, and Fe-PtNi prepared in Example 15 of the present invention in 0.1 mol / L HClO 4 ORR polarization curve of the solution. Detailed Embodiments

[0037] The technical solutions of the present invention will be further described and illustrated below through specific embodiments in conjunction with the accompanying drawings.

[0038] Example 1

[0039] (1) 0.06 mmol of platinum acetylacetonate, 0.024 mmol of nickel acetylacetonate, 0.006 mmol of titanium acetylacetonate and 40 mg of carbon black of type ECP-600 were added to 50 mL of acetone, and ultrasonic dispersion was carried out. Subsequently, natural stirring was carried out at room temperature until dry.

[0040] (2) The material obtained in step (1) was transferred to a mortar and ground until uniform. Then the obtained powder was transferred to a quartz boat and thermally annealed in a mixed atmosphere of argon and hydrogen (the volume ratio of argon to hydrogen is 90:10). The temperature was slowly raised to 800 °C at a heating rate of 10 °C / min, held at 800 °C for 3 h, and then cooled to room temperature to obtain the intermetallic compound Ti-Pt 3 Ni.

[0041] The Ti-Pt 3 Ni prepared in this example was subjected to X-ray powder diffraction detection. The detection results are as Figure 1 shown: The superlattice peak near 33° proved that an ordered intermetallic compound phase was synthesized in this example.

[0042] Example 2

[0043] Basically the same as Example 1, the difference is that: the molar ratio of nickel acetylacetonate to titanium acetylacetonate in step (1) was adjusted to 9:1 to obtain Ti-Pt 3 Ni-1.

[0044] The Ti-Pt 3 Ni-1 prepared in this example was subjected to X-ray powder diffraction detection. The detection results are as Figure 1 shown, and the superlattice peak near 33° proved that an ordered intermetallic compound phase was synthesized in this example.

[0045] Example 3

[0046] Basically the same as Example 1, the difference is that: the molar ratio of nickel acetylacetonate to titanium acetylacetonate in step (1) was adjusted to 7:3 to obtain Ti-Pt 3 Ni-2.

[0047] The Ti-Pt 3 Ni-2 prepared in this example was subjected to X-ray powder diffraction detection. The detection results are as Figure 1 shown: The superlattice peak near 33° proved that an ordered intermetallic compound phase was synthesized in this example.

[0048] Perform aberration-corrected high-angle annular dark-field imaging - scanning transmission electron microscopy (HAADF-STEM) detection with atomic resolution on the Ti-Pt 3 Ni-2 obtained in this example. The detection results are as Figure 2 shown: From the spherical aberration image, the clearly visible Pt, Ni, and Ti elements arranged in an ordered pattern of light and dark prove that an ordered intermetallic compound phase was synthesized in this example.

[0049] Perform elemental analysis detection on the Ti-Pt 3 Ni-2 obtained in this example. The detection results are as Figure 3 shown: Elemental analysis proves that the Ti-Pt 3 Ni-2 synthesized in this example contains Pt, Ni, and Ti elements.

[0050] Perform conventional transmission electron microscopy (TEM) detection on the Ti-Pt 3 Ni-2 obtained in this example. The detection results are as Figure 4 shown: The average particle size of Ti-Pt 3 Ni-2 is 3.04 nm.

[0051] Example 4

[0052] Basically the same as Example 1, except that: adjust the molar ratio of nickel acetylacetonate to titanium acetylacetonate in step (1) to 6:4 to obtain Ti-Pt 3 Ni-3.

[0053] Perform X-ray powder diffraction (XRD) detection on the Ti-Pt 3 Ni-3 obtained in this example. The detection results are as Figure 1 shown: The superlattice peak near 33° proves that an ordered intermetallic compound phase was synthesized in this example.

[0054] Example 5

[0055] Basically the same as Example 1, except that: adjust the molar ratio of nickel acetylacetonate to titanium acetylacetonate in step (1) to 10:0 to obtain Pt 3 Ni.

[0056] Perform X-ray powder diffraction (XRD) detection on the Pt 3 Ni obtained in this example. The detection results are as Figure 4 shown: The superlattice peak near 33° proves that an ordered intermetallic compound phase was synthesized in this example.

[0057] Perform conventional transmission electron microscopy (TEM) detection on the Pt 3 Ni obtained in this example. The detection results are as Figure 5 shown: Pt 3The average particle size of Ni is 3.10 nm.

[0058] Example 6

[0059] Basically the same as Example 1, except that: titanium acetylacetonate in step (1) is replaced with an equimolar amount of vanadium acetylacetonate to obtain V-Pt 3 Ni.

[0060] For the V-Pt 3 Ni prepared in this example, X-ray powder diffraction detection was carried out. The detection results are as Figure 6 shown: The superlattice peak near 33° proves that an ordered intermetallic compound phase was synthesized in this example.

[0061] Example 7

[0062] Basically the same as Example 1, except that: titanium acetylacetonate in step (1) is replaced with an equimolar amount of chromium nitrate to obtain Cr-Pt 3 Ni.

[0063] For the Cr-Pt 3 Ni prepared in this example, X-ray powder diffraction detection was carried out. The detection results are as Figure 6 shown: The superlattice peak near 33° proves that an ordered intermetallic compound phase was synthesized in this example.

[0064] Example 8

[0065] Basically the same as Example 1, except that: titanium acetylacetonate in step (1) is replaced with an equimolar amount of manganese acetylacetonate to obtain Mn-Pt 3 Ni.

[0066] For the Mn-Pt 3 Ni prepared in this example, X-ray powder diffraction detection was carried out. The detection results are as Figure 6 shown: The superlattice peak near 33° proves that an ordered intermetallic compound phase was synthesized in this example.

[0067] Example 9

[0068] Basically the same as Example 1, except that: titanium acetylacetonate in step (1) is replaced with an equimolar amount of iron acetylacetonate to obtain Fe-Pt 3 Ni.

[0069] For the Fe-Pt 3 Ni prepared in this example, X-ray powder diffraction detection was carried out. The detection results are as Figure 6 shown: The superlattice peak near 33° proves that an ordered intermetallic compound phase was synthesized in this example.

[0070] Example 10

[0071] Basically the same as Example 1, except that: the molar amounts of platinum acetylacetonate, nickel acetylacetonate and titanium acetylacetonate are adjusted to 0.06 mmol, 0.06 mmol and 0.015 mmol respectively to obtain Ti-PtNi.

[0072] The Ti-PtNi prepared in this example was subjected to X-ray powder diffraction detection. The detection results are as Figure 7 shown: It can be determined from the superlattice peak near 33° that an ordered intermetallic compound phase was synthesized in this example.

[0073] Example 11

[0074] Basically the same as Example 10, except that: the molar ratio of nickel acetylacetonate to titanium acetylacetonate is adjusted to 10:0 to obtain PtNi.

[0075] The PtNi prepared in this example was subjected to X-ray powder diffraction detection. The detection results are as Figure 7 shown: Since no superlattice peak near 33° was detected, it can be determined that a phase with disordered structure was synthesized in this example.

[0076] Example 12

[0077] Basically the same as Example 10, except that: titanium acetylacetonate is replaced with an equimolar amount of vanadium acetylacetonate to obtain V-PtNi.

[0078] The V-PtNi prepared in this example was subjected to X-ray powder diffraction detection. The detection results are as Figure 7 shown: It can be determined from the superlattice peak near 33° that an intermetallic compound phase was synthesized in this example.

[0079] Example 13

[0080] Basically the same as Example 10, except that: titanium acetylacetonate is replaced with an equimolar amount of chromium acetylacetonate to obtain Cr-PtNi.

[0081] The Cr-PtNi prepared in this example was subjected to X-ray powder diffraction detection. The detection results are as Figure 7 shown: It can be determined from the superlattice peak near 33° that an intermetallic compound phase was synthesized in this example.

[0082] Example 14

[0083] Basically the same as Example 10, except that: titanium acetylacetonate is replaced with an equimolar amount of manganese acetylacetonate to obtain Mn-PtNi.

[0084] The Mn-PtNi obtained in this example was subjected to X-ray powder diffraction detection. The detection results are as Figure 7 shown: From the superlattice peak near 33°, it can be determined that the intermetallic compound phase was synthesized in this example.

[0085] Example 15

[0086] Basically the same as Example 10, the difference is that: titanium acetylacetonate was replaced with an equimolar amount of iron acetylacetonate to obtain Fe-PtNi.

[0087] The Fe-PtNi obtained in this example was subjected to X-ray powder diffraction detection. The detection results are as Figure 7 shown: From the superlattice peak near 33°, it can be determined that the intermetallic compound phase was synthesized in this example.

[0088] Comparative Example 1

[0089] This comparative example used a commercial platinum-carbon catalyst with a platinum mass percentage of 20%.

[0090] Performance detection

[0091] The catalysts prepared in each example of the present invention and the comparative example were subjected to activity detection for acidic oxygen reduction. The specific method was as follows:

[0092] The catalyst was electrochemically tested under a three-electrode system. A saturated calomel electrode was selected as the reference electrode, a graphite rod electrode was used as the counter electrode, and a rotating disk electrode was used as the working electrode. When preparing the catalyst slurry, 1 mg of the catalyst was added to 500 μL of deionized water, 500 μL of isopropanol, and 10 μL of Nafion solution. And ultrasonic dispersion was carried out to obtain the catalyst slurry. Subsequently, 10 μL of the catalyst slurry was dropped onto the rotating disk electrode.

[0093] The catalyst was evaluated by cyclic voltammetry (CV) and linear sweep voltammetry (LSV). All potentials were relative to the reversible hydrogen electrode. The catalyst was first subjected to a CV scan between 0.05 and 1.05 V at 250 mV / s in a nitrogen-saturated 0.1 mol / L perchloric acid solution until a stable CV curve was obtained. Then in an oxygen-saturated 0.1 M HClO 4 solution, the scan rate was 10 mV / s, the rotation rate was 1600 revolutions per minute, and the oxygen reduction polarization curve was recorded.

[0094] To evaluate the stability of the catalyst, an accelerated durability test (ADT) was carried out in an O 2 -saturated 0.1 M HClO 4 solution, the potential range was from 0.6 V to 1.0 V, and the scan rate was 0.1 V s -1 .

[0095] Figure 8 For Comparative Example 1, Ti-Pt prepared in Example 1 of the present invention 3 Ni, Pt prepared in Example 5 3 Ni, V-Pt prepared in Example 6 3 Ni, Cr-Pt prepared in Example 7 3 Ni, Mn-Pt prepared in Example 8 3 Ni and Fe-Pt prepared in Example 9 3 Ni in 0.1 mol / L HClO 4 solution ORR polarization curve graph. From Figure 8 it can be seen that the half-wave potential of the Ti-Pt 3 Ni catalyst prepared in Example 1 is higher than that of Comparative Example 1, Pt 3 Ni prepared in Example 5, V-Pt 3 Ni prepared in Example 6, Cr-Pt 3 Ni prepared in Example 7, Mn-Pt 3 Ni prepared in Example 8 and Fe-Pt 3 Ni prepared in Example 9.

[0096] Table 1 is for Comparative Example 1, Ti-Pt prepared in Example 1 of the present invention 3 Ni, Ti-Pt prepared in Example 2 3 Ni-1, Ti-Pt prepared in Example 3 3 Ni-2, Ti-Pt prepared in Example 4 3 Ni-3, Pt 3 Ni prepared in Example 5, V-Pt 3 Ni prepared in Example 6, Cr-Pt 3 Ni prepared in Example 7, Mn-Pt 3 Ni prepared in Example 8 and Fe-Pt 3 Ni in 0.1 mol / L HClO 4 solution ORR activity summary table, including mass-specific activity and area-specific activity.

[0097] Table 1

[0098]

[0099]

[0100] Combined with Table 1, it can be seen that transition metal doping can improve the ORR activity of Pt 3 Ni, and the mass-specific activity and area-specific activity of the Ti-Pt 3 Ni catalyst are higher than those of Pt 3Ni, V-Pt prepared in Example 6 3 Ni, Cr-Pt prepared in Example 7 3 Ni, Mn-Pt prepared in Example 8 3 Ni and Fe-Pt prepared in Example 9 3 Ni. By adjusting the composition of the precursor, Ti-Pt prepared in Example 2 was obtained 3 Ni-1, Ti-Pt prepared in Example 3 3 Ni-2, Ti-Pt prepared in Example 4 3 Ni-3, among which Ti-Pt prepared in Example 3 3 Ni-2 is the best, and the mass specific activity reaches 1.35 A mg Pt -1 .

[0101] Figure 9 Fig. (a) is the linear sweep voltammogram of the commercial Pt / C catalyst before and after 30,000-cycle durability test, and Fig. (b) is the comparison diagram of mass specific activity and area specific activity. The mass specific activity of the commercial Pt / C catalyst decreased from 0.17 A mg Pt -1 to 0.04 A mg Pt -1 after 30,000-cycle durability test, with a decrease of 76.47%.

[0102] Figure 10 Fig. (a) is the linear sweep voltammogram of the Pt 3 Ni catalyst prepared in Example 5 before and after 30,000-cycle durability test, and Fig. (b) is the comparison diagram of mass specific activity and area specific activity. The mass specific activity of the Pt 3 Ni catalyst prepared in Example 5 decreased from 0.59 A mg Pt -1 to 0.20 A mg Pt -1 after 30,000-cycle durability test, with a decrease of 66.10%

[0103] Figure 11 Fig. (a) is the linear sweep voltammogram of the Ti-Pt 3 Ni-2 catalyst prepared in Example 3 before and after 30,000-cycle durability test, and Fig. (b) is the comparison diagram of mass specific activity and area specific activity. The mass specific activity of Ti-Pt 3 Ni-2 decreased from 1.35 A mg Pt -1 to 0.98 A mg Pt -1 after 30,000-cycle durability test, with only a loss of 27.41%. It can be seen that Ti-Pt 3The stability of the Ni-2 catalyst is far better than that of Pt 3 Ni and commercial platinum-carbon catalysts.

[0104] Figure 12 For Comparative Example 1, Ti-PtNi prepared in Example 10 of the present invention, PtNi prepared in Example 11, V-PtNi prepared in Example 12, Cr-PtNi prepared in Example 13, Mn-PtNi prepared in Example 14, and Fe-PtNi prepared in Example 15 in 0.1 mol / L HClO 4 The ORR polarization curve in the solution. From Figure 12 It can be seen that the half-wave potential of the Fe-PtNi catalyst prepared in Example 15 is higher than that of Ti-PtNi prepared in Example 10, PtNi prepared in Example 11, V-PtNi prepared in Example 12, Cr-PtNi prepared in Example 13, and Mn-PtNi prepared in Example 14.

[0105] Table 2 shows the summary table of the ORR activities of Comparative Example 1, Ti-PtNi prepared in Example 10 of the present invention, PtNi prepared in Example 11, V-PtNi prepared in Example 12, Cr-PtNi prepared in Example 13, Mn-PtNi prepared in Example 14, and Fe-PtNi prepared in Example 15 in 0.1 mol / L HClO 4 solution, including the mass-specific activity and the area-specific activity. Combining Table 2, it can be seen that the doping of transition metals helps to improve the ORR activity of PtNi, and the mass-specific activity and area-specific activity of the Fe-PtNi catalyst are higher than those of Comparative Example 1, Ti-PtNi prepared in Example 10, PtNi prepared in Example 11, V-PtNi prepared in Example 12, Cr-PtNi prepared in Example 13, and Mn-PtNi prepared in Example 14.

[0106] Table 2

[0107] Catalyst <![CDATA[Specific activity by mass (A mg Pt -1 )]]> <![CDATA[Area specific activity (mA cm -2 ) <!-- 7 -->]]> Pt / C 0.17 0.25 PtNi 0.85 1.21 Ti-PtNi 0.55 1.06 V-PtNi 1.1 1.43 Cr-PtNi 1.11 1.21 Mn-PtNi 0.96 1.31 Fe-PtNi 1.25 1.49

[0108] The above is only the preferred embodiment of the present invention, so the scope of implementation of the present invention cannot be limited thereby. That is, equivalent changes and modifications made according to the scope of the present invention patent and the content of the specification should still fall within the scope covered by the present invention.

Claims

1. A method for preparing a transition metal-doped platinum-nickel intermetallic compound fuel cell catalyst, characterized in that: The steps include: (1) adding a platinum precursor, a nickel precursor, a transition metal precursor and carbon black into acetone, and performing ultrasonic dispersion, and then stirring at room temperature until dry; (2) Grinding the material obtained in step (1) until it is uniform, and then heat treating the obtained powder, wherein the heat treatment conditions are: heating from room temperature to 700-900° C. in an 8-12 vol% H2 / Ar atmosphere, and keeping the temperature for 2-4 hours; cooling to room temperature after the heat treatment to obtain the transition metal-doped platinum-nickel intermetallic compound fuel cell catalyst, wherein the molar ratio of nickel to transition metal is 6-9:1-4, and the molar ratio of nickel to platinum is 0.4-1:

1.

2. The preparation method according to claim 1, characterized in that: The transition metal is selected from titanium, vanadium, chromium, manganese and iron.

3. The preparation method according to claim 2, characterized in that: The transition metal precursor is selected from titanium acetylacetonate, vanadium acetylacetonate, chromium acetylacetonate, manganese acetylacetonate, iron acetylacetonate, titanium phthalocyanine, vanadyl phthalocyanine, chromium phthalocyanine, manganese phthalocyanine, iron phthalocyanine, chromium nitrate, manganese nitrate and iron nitrate.

4. The preparation method according to claim 1, characterized in that: The platinum precursor is selected from platinum acetylacetonate, chloroplatinic acid, platinum nitrate, (1,5-cyclooctadiene) dimethylplatinum, dichloro(1,5-cyclooctadiene) platinum, trimethyl(methylcyclopentadienyl) platinum, potassium tetrachloroplatinate, potassium hexachloroplatinate and platinum dichloride.

5. The preparation method according to claim 1, characterized in that: The nickel precursor is selected from nickel acetylacetonate, nickel phthalocyanine, 2,3-naphthylcyanide nickel, nickel nitrate and nickel chloride.

6. The preparation method according to claim 1, characterized in that: The carbon black is selected from BP2000, ECP-600, ECP-300 and XC-72.

7. The preparation method according to claim 1, characterized in that: The transition metal precursor is selected from titanium acetylacetonate, vanadium acetylacetonate, chromium acetylacetonate, manganese acetylacetonate, iron acetylacetonate, titanium phthalocyanine, vanadium phthalocyanine, chromium phthalocyanine, manganese phthalocyanine, iron phthalocyanine, chromium nitrate, manganese nitrate and iron nitrate; the platinum precursor is selected from platinum acetylacetonate, chloroplatinic acid, platinum nitrate, (1,5-cyclooctadiene) dimethyl platinum, dichloro (1,5-cyclooctadiene) platinum, trimethyl (methylcyclopentadienyl) platinum, potassium tetrachloroplatinate, potassium hexachloroplatinate and platinum dichloride; the nickel precursor is selected from nickel acetylacetonate, nickel phthalocyanine, 2,3-naphthyl cyanide nickel, nickel nitrate and nickel chloride; the carbon black is selected from BP2000, ECP-600, ECP-300 and XC-72.

8. The preparation method according to claim 7, characterized in that: The platinum precursor is platinum acetylacetonate; the nickel precursor is nickel acetylacetonate; the transition metal precursor is selected from titanium acetylacetonate, vanadium acetylacetonate, chromium acetylacetonate, manganese acetylacetonate and iron acetylacetonate; the carbon black is ECP-600.

9. Use of the transition metal-doped platinum-nickel intermetallic compound fuel cell catalyst prepared by the preparation method according to any one of claims 1 to 8 in the preparation of a fuel cell.

10. A fuel cell, characterized in that: The invention discloses a transition metal-doped platinum-nickel intermetallic compound fuel cell catalyst prepared by the preparation method according to any one of claims 1 to 8.

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