Preparation method and application of palladium transition metal alloy loaded biomass carbon material

Abstract

The invention discloses a preparation method and application of a palladium transition metal alloy loaded biomass carbon material, and is characterized in that the preparation method comprises the following steps: by taking catkin as a carbon source and taking chloropalladic acid and metal salt as raw materials, synthesizing materials by adopting a microwave reduction method, and preparing the palladium transition metal alloy loaded biomass carbon material; the palladium transition metal alloy loaded biomass carbon material is used for preparing a working electrode and can be applied to a proton exchange membrane fuel cell and a glucose biological cell. According to the method, common catkin is selected as a carbon source, cheap transition metal is adopted as a raw material, the cost is reduced, meanwhile, the adopted synthesis method is simple, the process is stable and reliable, certain operability is achieved, and meanwhile the prepared catalyst has obviously excellent ethanol and glucose oxidation electrocatalytic activity.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of material preparation, in particular to a preparation method of a palladium-transition metal alloy loaded biomass carbon material and application thereof. BACKGROUND

[0002] In recent years, many research groups have consciously increased their efforts to design and develop advanced materials with nanostructures. These materials have been widely studied as electrode materials for electrochemical applications. Nanostructured carbon materials have been recognized as one of the most important electrode materials in the field of catalyst supports. Among these carbon-based materials, carbon nanotubes, graphene and carbon nanofibers are widely used as electrocatalyst supports.

[0003] In addition to the above carbon materials, hollow carbon tubes have attracted attention due to their high specific surface area, high electrical conductivity inherent to carbon materials, light weight, high structural stability, high porosity.

[0004] As a kind of biomass material, catkins is a waste in spring and summer, which not only cannot produce any economic benefits, but also seriously affects air quality. The flying catkins not only harms human health, but also spreads as a carrier of pollutants (dust and bacteria, etc.), making people suffer from various diseases and discomfort such as cough, asthma, runny nose and skin allergy. Moreover, the flying catkins also affects the line of sight and increases the risk of traffic accidents, and because it is extremely flammable, it also increases the risk of fire. However, surprisingly, the thick-walled tissue of catkin skin contains a large amount of nutrients such as cellulose, nitrogen-containing substances, polysaccharides, monosaccharides, proteins and oils. As a natural fiber resource, the direct pyrolysis of catkins can produce one-dimensional (1D) hollow carbon tube structures, which can provide abundant surface area for MxOy. It can also act as a dispersant for active species, inhibiting their aggregation and improving their utilization. In particular, one-dimensional hollow tubular structures are considered to be a very promising hollow microstructure for promoting mass transfer of electrolytes, thereby ensuring rapid ion transport

[0005] The present application relates to the technical field of material preparation, in particular to a preparation method of a palladium-transition metal alloy loaded biomass carbon material and application thereof. SUMMARY

[0006] The present application aims to synthesize materials by a simple microwave reduction method, select catkins as a carbon source, design and synthesize a palladium-transition metal alloy loaded biomass carbon material, reduce its cost, and the hollow structure makes the catalyst have a larger specific surface area and porosity, while also having excellent structural stability to ensure the service life of the catalyst, and is beneficial to the rapid transmission of substances to improve the catalytic rate; the prepared catalyst has high catalytic activity and obvious excellent ethanol and glucose oxidation electrocatalytic activity for ethanol and glucose detection.

[0007] In order to achieve the above technical effects, the application designs a preparation method of a palladium transition metal alloy loaded biomass carbon material, characterized in that the method comprises the following steps:

[0008] A preparation method of a palladium transition metal alloy loaded biomass carbon material, characterized in that the method comprises the following steps:

[0009] S1, 0.15-0.25 g of clean and uniform willow catkins are weighed, and the willow catkins are annealed at 800 DEG C for 2 h under N2 atmosphere to obtain hollow carbon tubes;

[0010] S2, the obtained hollow carbon tubes are dispersed into 15-25 ml of ethylene glycol solution to obtain a mixed solution after sufficient stirring;

[0011] S3, chloropalladic acid and metal salt are added into the mixed solution obtained in S2 at a molar ratio of Pd:M=1:1, and mixed at room temperature, and stirred for 8-12 min to obtain five groups of precursor solutions; wherein M is one of Fe, Co, Ni, Cu and Mn;

[0012] S4, the five groups of precursor solutions are respectively placed into a centrifuge, and the suspension is separated at 7500-8500 r / min, and then washed and centrifuged with ultrapure water for multiple times to obtain five groups of initial liquids;

[0013] S5, the five groups of initial liquids are placed into a vacuum oven at 55-65 DEG C and dried for 35-37 h to obtain dried precursors;

[0014] S6, the dried precursors are placed into a microwave oven, the power is adjusted to make the temperature in the oven reach 300 DEG C, and heating reduction is performed to obtain a palladium transition metal alloy loaded biomass carbon material (PdM-PCF).

[0015] Further, in S3, the metal salt is one of iron acetate, cobalt acetate, nickel acetate, copper acetate and manganese acetate.

[0016] Further, the palladium transition metal alloy loaded biomass carbon material has a hollow tubular morphology; the Pd in the palladium transition metal alloy loaded biomass carbon material exists in the form of a PdM alloy phase; wherein M is one of Fe, Co, Ni, Cu and Mn.

[0017] Another object of the application is to provide an application of a palladium transition metal alloy loaded biomass carbon material, characterized in that the palladium transition metal alloy loaded biomass carbon material can be applied to a proton exchange membrane fuel cell and a glucose bioelectricity cell.

[0018] Further, the specific application is as follows:

[0019] A, the ultrapure water and the Nafion solution with a concentration of 5% are mixed in a proportion of 9-18:1-2 by volume ratio to prepare a dispersion environment solution, and the sample is mixed with the dispersion solution in a proportion of 3 mg / ml to obtain a dispersion solution;

[0020] B, the dispersion solution is ultrasonically dispersed for 1h to obtain a homogeneous catalyst ink, 10 μL of the dispersion solution is taken and dropped on the surface of a glassy carbon electrode to prepare a working electrode, and the working electrode is naturally dried and used for testing the oxidation activity of ethanol and glucose;

[0021] C, the oxidation activity of ethanol and glucose is tested in an electrolyte saturated with N2.

[0022] Further, the electrolyte is one of 0.1M KOH, 0.1M KOH+1M CH3CH2OH and 0.1M KOH+50mM glucose.

[0023] The present application has the following beneficial effects:

[0024] The present application selects common ordinary catkins as a carbon source and uses cheap transition metals as raw materials, thereby reducing the cost, and the synthesis method is simple, the process is stable and reliable, and has certain operability; the catalyst prepared according to the method has excellent electrocatalytic activity and certain applicability, and therefore, when applied to detect the oxidation activity of ethanol and glucose, it exhibits excellent electrocatalytic activity, thereby providing a basis for the application of the catalyst to proton exchange membrane fuel cells and glucose bio-batteries. BRIEF DESCRIPTION OF DRAWINGS

[0025] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following will briefly introduce the drawings needed to be used in the embodiment description. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can also be obtained by those skilled in the art without creative labor.

[0026] Figure 1 is an electron microscope image of the catalyst of the present application embodiment 1;

[0027] Figure 2 is an electron microscope image of the catalyst of the present application embodiment 2;

[0028] Figure 3 is a transmission electron microscope image of the catalyst of the present application embodiment 1;

[0029] Figure 4 is a transmission electron microscope image of the catalyst of the present application embodiment 2;

[0030] Figure 5 is an X-ray diffraction pattern of the catalysts of the present application embodiments 1, 2, 3 and 4;

[0031] Figure 6 is the cyclic voltammogram of the catalyst of the present application embodiment 1, 2;

[0032] Figure 7 is the cyclic voltammogram of the catalyst of the present application embodiment 3, 4. DETAILED DESCRIPTION

[0033] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the protection scope of the present application.

[0034] Embodiment 1

[0035] A preparation method of a PdFe alloy loaded biomass carbon material, the specific steps are as follows:

[0036] (1) Take 0.2 g of clean and uniform willow catkins, and anneal the willow catkins in an N2 atmosphere at 800 DEG C for 2 h to obtain hollow carbon tubes;

[0037] (2) The obtained hollow carbon tubes are dispersed into 20 ml of an ethylene glycol solution and fully stirred to obtain a mixed solution;

[0038] (3) Chloropalladic acid and iron acetate are added into the obtained mixed solution in a Pd: Fe = 1: 1 ratio and mixed at room temperature, and fully stirred for 10 min to obtain a PdFe-PCF catalyst precursor solution;

[0039] (4) The suspension is separated at 8000 rpm, and then washed / centrifuged with ultrapure water for multiple times, and then placed into a 60 DEG C vacuum oven for drying for 36 h;

[0040] (5) The obtained dried precursor is placed into a microwave oven, the power is adjusted so that the temperature in the oven reaches 300 DEG C, and heating reduction is performed to obtain a PdFe-PCF.

[0041] Embodiment 2

[0042] A preparation method of a PdCo alloy loaded biomass carbon material, the specific steps are as follows:

[0043] (1) Take 0.2 g of clean and uniform willow catkins, and anneal the willow catkins in an N2 atmosphere at 800 DEG C for 2 h to obtain hollow carbon tubes;

[0044] (2) The obtained hollow carbon tubes are dispersed into 20 ml of an ethylene glycol solution and fully stirred to obtain a mixed solution;

[0045] (3) Chloropalladic acid and cobalt acetate are added into the obtained mixed solution in a ratio of Pd:Co=1:1, mixed at room temperature, and stirred fully for 10 min to obtain a PdCo-PCF catalyst precursor solution;

[0046] (4) The suspension is separated at 8000 rpm, then washed / centrifuged continuously multiple times with ultrapure water, and then placed in a vacuum oven at 60°C for drying for 36 h;

[0047] (5) The obtained dried precursor is placed in a microwave oven, the power is adjusted so that the temperature in the oven reaches 300°C, and heating reduction is performed to obtain a PdCo-PCF.

[0048] Example 3

[0049] A preparation method of a PdMn alloy loaded biomass carbon material, and the specific steps are as follows:

[0050] (1) 0.2 g of clean and uniform willow catkins are taken, annealed at 800°C for 2 h in an N2 atmosphere, and then fired to obtain hollow carbon tubes;

[0051] (2) The obtained hollow carbon tubes are dispersed into 20 ml of an ethylene glycol solution and stirred fully to obtain a mixed solution;

[0052] (3) Chloropalladic acid and nickel acetate are added into the obtained mixed solution in a ratio of Pd:Mn=1:1, mixed at room temperature, and stirred fully for 10 min to obtain a PdMn-PCF catalyst precursor solution;

[0053] (4) The suspension is separated at 8000 rpm, then washed / centrifuged continuously multiple times with ultrapure water, and then placed in a vacuum oven at 60°C for drying for 36 h;

[0054] (5) The obtained dried precursor is placed in a microwave oven, the power is adjusted so that the temperature in the oven reaches 300°C, and heating reduction is performed to obtain a PdMn-PCF.

[0055] Example 4

[0056] A preparation method of a PdCu alloy loaded biomass carbon material, and the specific steps are as follows:

[0057] (1) 0.2 g of clean and uniform willow catkins are taken, annealed at 800°C for 2 h in an N2 atmosphere, and then fired to obtain hollow carbon tubes;

[0058] (2) The obtained hollow carbon tubes are dispersed into 20 ml of an ethylene glycol solution and stirred fully to obtain a mixed solution;

[0059] (3) Chloropalladic acid and cobalt acetate are added into the obtained mixed solution in a ratio of Pd:Cu=1:1, mixed at room temperature, and stirred fully for 10 min to obtain a PdCu-PCF catalyst precursor solution;

[0060] (4) Separating the suspension at 8000 rpm, then washing / centrifuging with ultrapure water for several times, and drying in a vacuum oven at 60°C for 36h;

[0061] (5) Placing the obtained dried precursor into a microwave oven, adjusting the power to make the temperature in the oven reach 300°C, and heating to reduce to obtain PdCu-PCF.

[0062] 1. Electron microscope image analysis

[0063] Figure 1 and 2 Electron microscope images of hollow carbon tube supported transition metal Pd alloy catalysts prepared in Examples 1 and 2 of the present application; as can be seen from the figures, hollow carbon tubes are successfully formed, and transition metals and Pd are successfully supported on the hollow carbon tubes.

[0064] 2. Transmission electron microscope image analysis

[0065] Figure 3 and 4 Transmission electron microscope images of hollow carbon tube supported transition metal Pd alloy catalysts prepared in Examples 1 and 2 of the present application. As can be seen from the figures, Fe / Co nanoparticles are uniformly dispersed on the surface of the hollow carbon tubes.

[0066] 3. X-ray diffraction analysis

[0067] Figure 5 X-ray diffraction patterns of catalyst samples prepared in Examples 1, 2, 3 and 4 of the present application. As can be seen from the figures, the characteristic diffraction peaks of metallic Pd are shifted, indicating that Pd exists in the form of PdM (M = Fe, Co, Ni, Cu, Mn) alloy.

[0068] 3. Performance analysis

[0069] Figure 6 Electrochemical performance diagrams of catalyst samples prepared in Examples 1 and 2 of the present application. From Figure 6 it can be seen that the two catalysts prepared in the present application have obvious superior electrocatalytic activity for ethanol oxidation after the addition of ethanol.

[0070] Figure 7 Electrochemical performance diagrams of catalyst samples prepared in Examples 3 and 4 of the present application. From Figure 7 it can be seen that the two catalysts prepared in the present application have excellent electrocatalytic activity for oxidation after the addition of glucose.

Claims

1. A method for preparing a palladium transition metal alloy supported biomass carbon material, characterized in that, The method comprises the following steps: S1, 0.15-0.25 g of clean and uniform catkins are weighed and annealed at 800 DEG C for 2 h under N2 atmosphere to obtain hollow carbon tubes; S2, the obtained hollow carbon tubes are dispersed into 15-25 ml of ethylene glycol solution and fully stirred to obtain a mixed solution; S3, chloropalladic acid and metal salt are added into the mixed solution obtained in S2 at a molar ratio of Pd:M=1:1, mixed at room temperature, fully stirred for 8-12 min, and five groups of precursor solutions are obtained; wherein M is one of Fe, Co, Ni, Cu and Mn; S4, the five groups of precursor solutions are respectively placed into a centrifuge, the suspension is separated at 7500-8500 r / min, and then washed and centrifuged with ultrapure water for multiple times; five groups of initial liquids are obtained; S5, the obtained initial liquids are placed into a vacuum oven at 55-65 DEG C and dried for 35-37 h to obtain dried precursors; S6, the dried precursors are placed into a microwave oven, the power is adjusted to make the temperature in the oven reach 300 DEG C, and heating reduction is performed to obtain a palladium transition metal alloy loaded biomass carbon material (PdM-PCF).

2. The method according to claim 1, wherein the palladium transition metal alloy supported biomass carbon material is characterized in that, In S3, the metal salt is one of iron acetate, cobalt acetate, nickel acetate, copper acetate and manganese acetate.

3. The method according to claim 1, wherein the palladium transition metal alloy supported biomass carbon material is characterized in that, The palladium transition metal alloy loaded biomass carbon material has a hollow tubular morphology; in the palladium transition metal alloy loaded biomass carbon material, Pd exists in the form of PdM alloy phase; M is one of Fe, Co, Ni, Cu and Mn.

4. Use of a palladium transition metal alloy supported on a biomass carbon material, characterized in that, The palladium transition metal alloy loaded biomass carbon material can be applied to proton exchange membrane fuel cells and glucose bio-batteries.

5. The use of a palladium transition metal alloy supported on a biomass carbon material according to claim 4, characterized in that, Specific applications are as follows: A, ultrapure water and Nafion solution with a concentration of 5% are mixed at a volume ratio of 9-18:1-2 to prepare a dispersion environment solution, and the sample is mixed with the dispersion solution at a ratio of 3 mg / ml to obtain a dispersion solution; B, the dispersion solution is ultrasonically dispersed for 1 h to obtain a homogeneous catalyst ink, 10 μL of the dispersion solution is taken and dropped on the surface of a glassy carbon electrode to prepare a working electrode, and the working electrode is naturally dried and used for testing the oxidation activity of ethanol and glucose; C, the oxidation activity of ethanol and glucose is tested in an N2-saturated electrolyte.

6. The use of a palladium transition metal alloy supported on a biomass carbon material according to claim 5, characterized in that, The electrolyte is one of 0.1 M KOH, 0.1 M KOH+1 M CH3CH2OH and 0.1 M KOH+50 mM glucose.

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