Cerium phosphate cobalt catalyst, its preparation method and application
By preparing a cerium cobalt phosphate catalyst, the problems of insufficient selectivity and conversion rate in the electrocatalytic oxidation of alcohols and toluene derivatives into aldehydes were solved, achieving efficient oxidation to biomass aldehydes at room temperature and pressure, reducing costs and improving the economics of industrial applications.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- DALIAN UNIV OF TECH
- Filing Date
- 2026-03-23
- Publication Date
- 2026-06-05
Smart Images
Figure CN122144685A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of organic electrochemical catalysis, specifically to a cerium cobalt phosphate catalyst, its preparation method, and its application. Background Technology
[0002] Aldehydes and ketones play crucial roles in organic and pharmaceutical synthesis, being widely used in the synthesis of pharmaceuticals and other industrial chemicals. They are also a key focus in research aimed at converting carbohydrates, sugars, and other biomass-derived raw materials into high-value-added products. Therefore, developing methods to selectively oxidize alcohols or toluene derivatives to aldehydes or ketones while effectively preventing further over-oxidation to acids, esters, or other byproducts is of great significance in both pharmaceutical synthesis and industrial production. Although various reaction systems using metal catalysts such as silver, palladium, ruthenium, iron, copper, platinum, gold, iridium, and rhodium have been developed for the selective oxidation of alcohols and toluene derivatives to aldehydes or ketones, in industrial applications, alcohol oxidation reactions still primarily rely on traditional non-catalytic oxidation methods. Several reported non-catalytic oxidants, including chromium or manganese-based oxidants, high-valent iodine compounds, and activated sulfoxide reagents, can achieve the selective oxidation of alcohols. However, these oxidation systems typically suffer from high toxicity, high levels of hazardous waste generation, and high reaction costs. Against this backdrop, electrocatalytic oxidation has gradually attracted widespread attention due to its good economics, environmental friendliness and potential for large-scale application. It is considered a promising strategy to replace traditional thermochemical oxidation methods, which are usually carried out under mild conditions and can avoid the use of expensive or toxic chemical oxidants.
[0003] Primary alcohols derived from biomass (such as benzyl alcohol derivatives, furanol, glycerol and its derivatives) have diverse structures and are renewable sources, making them important precursors for the preparation of aldehydes and carboxylic acids. Liu et al. (Journal of the American Chemical Society, 2025, 147(12): 10339-10348.) disclosed PtZn-ZnO xPtZn alloy catalysts at the interface can achieve benzoic acid selectivity of up to 99.5% at a potential of approximately 0.725 V vs. RHE, while suppressing side reactions and improving energy efficiency. Pan et al. (Journal of Electroanalytical Chemistry, 2025, 996:119410.) synthesized a Ni3Co1-LDH / NF composite material by a one-step electrodeposition method. In 1M KOH electrolyte, the catalyst achieved almost complete conversion of benzyl alcohol with a benzoic acid selectivity of up to 99%. However, in K2CO3 electrolyte, although the conversion rate of benzyl alcohol was still high, the product distribution was significantly different, with benzaldehyde becoming the main product (selectivity 59%). Pei et al. (Nature Communications, 2024, 15(1): 5899.) disclosed a Ni3Co1-LDH / NF composite material rich in N2Co1-LDH / NF. 2+ A Pd / Ni(OH)2 electrocatalyst with an -O-Pd interface was used for the electrooxidation of 5-hydroxymethylfurfural (HMF) to 2,5-furandicarboxylic acid (FDCA). This catalyst achieved near 100% FDCA selectivity and complete HMF conversion in an alkaline electrolyte at a relatively low potential of about 0.6 V vs. RHE. However, in the prior art, the main product of the catalyst in the electrooxidation of alcohols is carboxylic acid, but carboxylic acid compounds have low added value and limited economic benefits. Aldehydes are products of incomplete oxidation of alcohols and are widely used in the synthesis of various chemicals, with higher economic value. Selectively oxidizing alcohols to aldehydes through electrooxidation remains a challenge.
[0004] p-Methoxytoluene is a basic alkyl aromatic hydrocarbon, and its side-chain methyl oxidation product, anisaldehyde, is an important precursor for the preparation of chemicals such as fragrances and pharmaceuticals. Torri et al. (The Journal of Organic Chemistry, 1982, 47(9): 1647-1652) disclosed a successful side-chain activation of p-methoxytoluene using an indirect electrochemical oxidation strategy in methanol solvent with cerium ammonium nitrate as the oxidation medium, achieving an anisaldehyde yield of up to 94%. Liao et al. (International Journal of Electrochemical Science, 2021, 16(1): 152021) disclosed a highly dispersed nano-Pt-MWCNTs electrocatalyst, which was used as the working electrode to directly oxidize p-methoxytoluene in an acetonitrile-water system at 40 °C, achieving 94% selectivity and 91% yield. Wu et al. (New Journal of Chemistry, 2022, 46(20): 9755-9761) disclosed the construction of a MnO2 / CNT / Gr composite three-dimensional electrocatalyst via deposition, which improved the adsorption efficiency of reactant functional groups by utilizing weakly polar carbon materials, ultimately achieving a Faradaic efficiency and selectivity of 81.03% and 82.73% for anisaldehyde, respectively. However, existing technologies still face bottlenecks in the electrocatalytic oxidation synthesis of aromatic aldehydes. Indirect oxidation methods are limited by the extremely large amount of cerium salt used and the difficulty in separation and recovery; direct oxidation methods require the use of noble metal catalysts and are prone to over-oxidation. How to further reduce the amount of noble metal used and suppress side reactions such as over-oxidation to acid are the main challenges facing this technology.
[0005] In summary, there is an urgent need to provide a catalyst and its preparation method for the electro-oxidation of alcohols and toluene derivatives into aldehydes with high selectivity and high conversion rate. Summary of the Invention
[0006] This invention addresses the technical problem of providing a catalyst for the electro-oxidation of alcohols and toluene derivatives into aldehydes with high selectivity and high conversion rate, as well as a method for its preparation.
[0007] To achieve the above objectives, the first aspect of the present invention provides a method for preparing a cobalt cerium phosphate catalyst, comprising the following steps:
[0008] S1. Add H3PO4 solution dropwise into a mixed aqueous solution of cerium nitrate and cobalt nitrate, and stir to obtain a white, homogeneous gel-like solution;
[0009] S2. Adjust the temperature of the white, homogeneous gel-like solution to 5-9 degrees Celsius using ammonia.
[0010] S3. The solution after pH adjustment in S2 is subjected to a hydrothermal reaction, naturally cooled to 20-30℃, centrifuged, and the precipitate is washed with distilled water and ethanol, and then vacuum dried to obtain the cerium cobalt phosphate catalyst.
[0011] A second aspect of the present invention provides a cerium cobalt phosphate catalyst prepared by the above preparation method, wherein the molar fraction of cobalt in the cerium cobalt phosphate catalyst is 3-10%.
[0012] The third aspect of the present invention provides the application of the above-mentioned cerium cobalt phosphate catalyst, wherein the cerium cobalt phosphate catalyst electrocatalyzes the oxidation of biomass alcohols and toluene derivatives to biomass aldehydes with a conversion rate of 98-99% and a selectivity of 80-92%.
[0013] The beneficial effects of this invention are as follows:
[0014] The cerium cobalt phosphate catalyst provided by this invention provides electrocatalytic oxidation of biomass alcohols, which can produce biomass aldehydes with high selectivity and high conversion rate in a green system at room temperature and pressure. This system is driven by electricity, avoiding the use of high temperature, high pressure and strong oxidants in traditional thermocatalysis. It has the advantages of green process, safety and controllability, and low energy consumption. The cerium cobalt phosphate catalyst provided is low in cost and widely available, which helps to reduce the overall cost of biomass aldehyde production and improve the feasibility and economy of industrial application. Attached Figure Description
[0015] Figure 1 This is the oxidation route diagram of furfuryl alcohol.
[0016] Figure 2 This is a diagram of the oxidation route of p-methoxytoluene.
[0017] Figure 3 The XRD characterization spectra of cobalt cerium phosphate (3% Co-CePO4, 5% Co-CePO4, 7.5% Co-CePO4, 10% Co-CePO4) used in this invention are shown.
[0018] Figure 4 The images shown are scanning electron microscope (SEM) images of the cerium cobalt phosphate catalyst used in this invention. Figure (a) shows 3% Co-CePO4, Figure (b) shows 5% Co-CePO4, Figure (c) shows 7.5% Co-CePO4, and Figure (d) shows 10% Co-CePO4.
[0019] Figure 5 The graphs show the selectivity and conversion rates of the electro-oxidation of furfuryl alcohol to furfural using the four cerium cobalt phosphate catalysts used in this invention. Sel. represents selectivity, and Con. represents conversion rate.
[0020] Figure 6The graph shows the conversion and selectivity of furfuryl alcohol to furfural by electro-oxidation of 5% Co-CePO4 at potentials of 1.87–1.93 V vs. RHE. Detailed Implementation
[0021] The endpoints and any values of the ranges disclosed herein are not limited to the precise ranges or values, and these ranges or values should be understood to include values close to these ranges or values. For numerical ranges, the endpoint values of the various ranges, the endpoint values of the various ranges and individual point values, and individual point values can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed herein.
[0022] The first aspect of this invention provides a method for preparing a cerium cobalt phosphate catalyst, comprising the following steps:
[0023] S1. Add H3PO4 solution dropwise into a mixed aqueous solution of cerium nitrate and cobalt nitrate, and stir to obtain a white, homogeneous gel-like solution;
[0024] S2. Adjust the pH of the white, homogeneous gel-like solution to 5-9 using ammonia.
[0025] S3. The solution after pH adjustment in S2 is subjected to a hydrothermal reaction, naturally cooled to 20-30℃, centrifuged, and the precipitate is washed with distilled water and ethanol, and then vacuum dried to obtain the cerium cobalt phosphate catalyst.
[0026] In this invention, cerium phosphate can realize Ce in its solid lattice. 3+ With Ce 4+ The flexible and reversible conversion of oxidation states, this dynamic valence cycle induces the generation of a large number of surface oxygen vacancies with extremely high catalytic activity. The electronic interaction between cobalt and cerium phosphate enhances the overall charge transport rate and optimizes the adsorption energy barrier of the intermediate.
[0027] According to the present invention, in step S1, the concentration of the H3PO4 solution is 0.1-1M;
[0028] In a mixed aqueous solution of cerium nitrate and cobalt nitrate, Ce 3+ The concentration was 0.03-0.09 M, Co 2+ The concentration is 0.001-0.006M;
[0029] H3PO4, Co 2+ and Ce 3+ The molar ratio is 1-2:0.03-0.1:1.
[0030] According to the present invention, in step S1, the stirring conditions include: stirring time of 1-2 hours and stirring frequency of 500-1000 RPM.
[0031] According to the present invention, in step S2, the mass concentration of the ammonia water is 10-25%.
[0032] According to the present invention, the conditions for the hydrothermal reaction include: the temperature of the hydrothermal reaction is 100-140°C.
[0033] According to the present invention, in step S3, the conditions for the hydrothermal reaction include: the hydrothermal reaction time is 8-24 h.
[0034] According to the present invention, in step S3, the conditions for centrifugal separation include: a centrifugal speed of 8000-12000 r / min and a centrifugal separation time of 5-15 min.
[0035] According to the present invention, in step S3, the conditions for vacuum drying include: a vacuum drying temperature of 50-80 °C and a vacuum drying time of 24-72 h.
[0036] A second aspect of the present invention provides a cerium cobalt phosphate catalyst prepared by the above preparation method, wherein the molar fraction of cobalt in the cerium cobalt phosphate catalyst is 3-10%.
[0037] The third aspect of the present invention provides the application of the above-mentioned cerium cobalt phosphate catalyst, wherein the cerium cobalt phosphate catalyst electrocatalyzes the oxidation of biomass alcohol to biomass aldehyde with a conversion rate of 98-99% and a selectivity of 80-89%.
[0038] The biomass alcohol includes any one of furfuryl alcohol, cinnamyl alcohol, and anisole.
[0039] The biomass aldehydes include any one of furfural, cinnamaldehyde, and anisaldehyde.
[0040] The toluene derivatives include p-methoxytoluene or p-propenyl anisole.
[0041] Test methods
[0042] The method of electrocatalytic oxidation of biomass alcohols is as follows:
[0043] A slurry was obtained by mixing 20 mg of cobalt cerium phosphate catalyst, 713 μL of ethanol, 237 μL of water, and 50 μL of Nafion 117 solution and then sonicating. The slurry was dropped onto pretreated carbon paper to obtain the anode. A platinum sheet was used as the cathode, an Hg / HgO electrode as the reference electrode, and KOH as the electrolyte. The reaction was carried out in a unipolar electrolytic cell. The concentration of KOH was 0.1 M. Biomass alcohol was added to the solution to obtain the electrolyte. The concentration of furfuryl alcohol in the electrolyte was 10 mM. Constant potential electrolysis was used to achieve the electrocatalytic oxidation of biomass alcohol to biomass aldehyde.
[0044] The electrolysis potential of the constant potential electrolysis is selected as follows: the potential after the electrolysis substrate begins to respond to the current. Before electrolysis, carbon paper loaded with cerium cobalt phosphate catalyst is activated by CV, and the selected potential is used for electrolysis.
[0045] The CV activation cycle is 15 cycles, the electrolytic potential of the constant potential electrolysis is 1.80-1.90 V vs. RHE, and the electrolysis temperature is 25℃.
[0046] The electrolytic oxidation of biomass alcohol to biomass aldehyde takes 6-12 hours.
[0047] The method for electrocatalytic oxidation of toluene derivatives is as follows:
[0048] A slurry was prepared by mixing 20 mg of cerium cobalt phosphate catalyst, 713 μL of ethanol, 237 μL of water, and 50 μL of Nafion 117 solution and then sonicating. The slurry was then dropped onto pretreated carbon paper to obtain the anode. A platinum sheet was used as the cathode, an Ag / AgCl electrode was used as the reference electrode, and a mixed phosphate buffer solution with a concentration of 0.3 M was used as the electrolyte in a unipolar electrolytic cell. A toluene derivative was added to the solution to obtain an electrolyte with a concentration of 5 mM. Electrolysis was performed using a constant potential to achieve the electrocatalytic oxidation of the toluene derivative to anisaldehyde.
[0049] The electrolysis potential of the constant potential electrolysis is selected as follows: the potential after the electrolysis substrate begins to respond to the current. Before electrolysis, carbon paper loaded with cerium cobalt phosphate catalyst is activated by CV, and the selected potential is used for electrolysis.
[0050] The CV activation cycle is 15 cycles, the electrolysis potential of the constant potential electrolysis is 1.90 V vs. RHE, and the electrolysis temperature is 25℃.
[0051] The electrolytic oxidation time for the toluene derivative to anisaldehyde is 6-12 h.
[0052] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Obviously, the embodiments described herein are only some embodiments of the present invention and are not intended to limit the present invention. All other embodiments implemented by those skilled in the art based on the embodiments of the present invention without creative improvements are within the protection scope of the present invention.
[0053] Unless otherwise specified, the following examples and comparative examples were conducted under conventional conditions. Unless otherwise specified, the reagents or instruments used were all commercially available products.
[0054] Example 1:
[0055] First, dissolve 1.8 mmol Ce(NO3)3·6H2O and 0.054 mmol Co(NO3)2·6H2O in 30 mL of water to prepare a 0.5 M H3PO4 solution. Take 3.6 mL of the H3PO4 solution and add it dropwise to a mixed aqueous solution of cerium nitrate and cobalt nitrate. Stir vigorously for 1 hour at a stirring frequency of 800 RPM to obtain a white, homogeneous gel-like solution.
[0056] The pH of the solution environment was adjusted to 7 using a 10% ammonia solution.
[0057] The mixture was placed in a polytetrafluoroethylene reactor and subjected to a hydrothermal reaction at 120°C for 24 hours, then naturally cooled to 25°C. The mixture was centrifuged, washed three times with distilled water and ethanol, and dried under vacuum at 60°C to obtain a white solid powder, which is cobalt cerium phosphate catalyst A1 (the molar fraction of cobalt in the cobalt cerium phosphate catalyst is 3%, named 3%Co-CePO4).
[0058] The cerium cobalt phosphate catalyst A1 (3% Co-CePO4) was characterized, and the XRD characterization pattern is shown below. Figure 3 As shown, the morphological characterization diagram is as follows: Figure 4 As shown in (a).
[0059] Example 2
[0060] First, dissolve 1.8 mmol Ce(NO3)3·6H2O and 0.09 mmol Co(NO3)2·6H2O in 30 mL of water to prepare a 0.5 M H3PO4 solution. Take 3.6 mL of the H3PO4 solution and add it dropwise to a mixed aqueous solution of cerium nitrate and cobalt nitrate. Stir vigorously for 1 hour at a stirring frequency of 800 RPM to obtain a white, homogeneous gel-like solution.
[0061] The pH of the solution environment was adjusted to 7 using a 10% ammonia solution.
[0062] The mixture was placed in a polytetrafluoroethylene reactor and subjected to a hydrothermal reaction at 120°C for 24 hours, then naturally cooled to 25°C. The mixture was centrifuged, washed three times with distilled water and ethanol, and dried under vacuum at 60°C to obtain a white solid powder, which is cobalt cerium phosphate catalyst A2 (the molar fraction of cobalt in the cobalt cerium phosphate catalyst is 5%, named 5%Co-CePO4).
[0063] The XRD characterization of the cerium cobalt phosphate catalyst A2 (5% Co-CePO4) is shown in the figure below. Figure 3 As shown, the morphological characterization diagram is as follows: Figure 4 As shown in (b).
[0064] Example 3
[0065] First, dissolve 1.8 mmol Ce(NO3)3·6H2O and 0.135 mmol Co(NO3)2·6H2O in 30 mL of water to prepare a 0.5 M H3PO4 solution. Take 3.6 mL of the H3PO4 solution and add it dropwise to a mixed aqueous solution of cerium nitrate and cobalt nitrate. Stir vigorously for 1 hour at a stirring frequency of 800 RPM to obtain a white, homogeneous gel-like solution.
[0066] The pH of the solution environment was adjusted to 7 using a 10% ammonia solution.
[0067] The mixture was placed in a polytetrafluoroethylene reactor and subjected to a hydrothermal reaction at 120°C for 24 hours, then naturally cooled to 25°C. The mixture was centrifuged, washed three times with distilled water and ethanol, and dried under vacuum at 60°C to obtain a white solid powder, which is cobalt cerium phosphate catalyst A3 (the molar fraction of cobalt in the cobalt cerium phosphate catalyst is 7.5%, named 7.5%Co-CePO4).
[0068] The XRD characterization of the cerium cobalt phosphate catalyst A3 (7.5% Co-CePO4) is shown in the figure below. Figure 3 As shown, the morphological characterization diagram is as follows: Figure 4 As shown in (c).
[0069] Example 4
[0070] First, dissolve 1.8 mmol Ce(NO3)3·6H2O and 0.18 mmol Co(NO3)2·6H2O in 30 mL of water to prepare a 0.5 M H3PO4 solution. Take 3.6 mL of the H3PO4 solution and add it dropwise to a mixed aqueous solution of cerium nitrate and cobalt nitrate. Stir vigorously for 1 hour at a stirring frequency of 800 RPM to obtain a white, homogeneous gel-like solution.
[0071] The pH of the solution environment was adjusted to 7 using a 10% ammonia solution.
[0072] The mixture was placed in a polytetrafluoroethylene reactor and subjected to a hydrothermal reaction at 120°C for 24 hours, then naturally cooled to 25°C. The mixture was centrifuged, washed three times with distilled water and ethanol, and dried under vacuum at 60°C to obtain a white solid powder, which is cobalt cerium phosphate catalyst A4 (the molar fraction of cobalt in the cobalt cerium phosphate catalyst is 10%, named 10%Co-CePO4).
[0073] The XRD characterization of the cerium cobalt phosphate catalyst A4 (10% Co-CePO4) is shown in the figure below. Figure 3 As shown, the morphological characterization diagram is as follows: Figure 4 As shown in (d).
[0074] Example 5
[0075] The cerium cobalt phosphate catalyst was prepared according to the method in Example 2, except that the pH of the solution environment was adjusted to 5 with ammonia water, and cerium cobalt phosphate catalyst A5 was obtained.
[0076] Example 6
[0077] The cerium cobalt phosphate catalyst was prepared according to the method in Example 2, except that the pH of the solution environment was adjusted to 9 with ammonia water, and cerium cobalt phosphate catalyst A6 was obtained.
[0078] Example 7
[0079] The cerium cobalt phosphate catalyst was prepared according to the method in Example 2, except that the hydrothermal reaction temperature was 100°C, and cerium cobalt phosphate catalyst A7 was obtained.
[0080] Example 8
[0081] The cerium cobalt phosphate catalyst was prepared according to the method in Example 2, except that the hydrothermal reaction temperature was 140°C, and cerium cobalt phosphate catalyst A8 was obtained.
[0082] Comparative Example 1
[0083] The cerium cobalt phosphate catalyst was prepared according to the method in Example 2, except that the pH of the solution environment was adjusted to 2 with ammonia water, and the cerium cobalt phosphate catalyst DA1 was obtained.
[0084] Comparative Example 2
[0085] The cerium cobalt phosphate catalyst was prepared according to the method in Example 2, except that the pH of the solution environment was adjusted to 12 with ammonia water, and the cerium cobalt phosphate catalyst DA2 was obtained.
[0086] Comparative Example 3
[0087] The cerium cobalt phosphate catalyst was prepared according to the method in Example 2, except that the hydrothermal reaction temperature was 90°C, and the cerium cobalt phosphate catalyst DA3 was obtained.
[0088] Comparative Example 4
[0089] The cerium cobalt phosphate catalyst was prepared according to the method in Example 2, except that the hydrothermal reaction temperature was 180°C, and the cerium cobalt phosphate catalyst DA4 was obtained.
[0090] Comparative Example 5
[0091] The cerium copper phosphate catalyst was prepared according to the method in Example 2, except that cobalt nitrate was replaced with copper nitrate to obtain the cerium copper phosphate catalyst DA5.
[0092] Comparative Example 6
[0093] The cerium nickel phosphate catalyst was prepared according to the method in Example 2, except that cobalt nitrate was replaced with nickel nitrate to obtain the cerium nickel phosphate catalyst DA6.
[0094] Electrochemical catalytic synthesis of furfural using catalysts A1-A8 and DA1-DA6
[0095] Carbon paper was acidified with concentrated nitric acid, sonicated with distilled water and anhydrous ethanol, and then 20 mg of prepared cerium cobalt phosphate catalyst, 713 μL of ethanol, 237 μL of water and 50 μL of nafion117 solution were mixed and sonicated until homogeneous, and then dropped onto the carbon paper to obtain the anode.
[0096] The reaction was carried out in a single electrolytic cell, with a platinum sheet as the counter electrode, an Hg / HgO electrode as the reference electrode, and carbon paper loaded with cerium cobalt phosphate as the anode. 0.1 mmol of furfuryl alcohol was added to 10 mL of 0.1 M KOH solution. Before electrolysis, the cells were activated by CV for 15 cycles until stable. Electrolysis was then performed at 1.90 V vs. RHE, 1.87 V vs. RHE, and 1.93 V vs. RHE.
[0097] Real-time sampling and monitoring of the reaction process were conducted. Reactants and products were quantified using standard samples via external standard method, and quantitative analysis was performed by high-performance liquid chromatography (HPLC). The conversion rate and selectivity of furfuryl alcohol to furfural via electrocatalysis using cerium cobalt phosphate catalysts A1-A3 are shown in the figure below. Figure 5 As shown.
[0098] Real-time sampling and monitoring of the reaction process were conducted. Reactants and products were quantified using standard samples via external standard method, and quantitative analysis was performed by high-performance liquid chromatography (HPLC). The conversion and selectivity of furfuryl alcohol to furfural by the cerium cobalt phosphate catalyst A2 at 1.87V vs. RHE, 1.90V vs. RHE, and 1.93V vs. RHE were as follows: Figure 6 As shown.
[0099] Electrocatalytic tests were performed on A1-A8 and DA1-DA6, and the results are shown in Table 1.
[0100] Table 1
[0101]
[0102] As shown in Table 1, the cerium cobalt phosphate catalyst provided by the present invention can effectively electrocatalytically oxidize biomass alcohols to biomass aldehydes.
[0103] Electrochemical catalysis of anisaldehyde was performed using catalysts A1-A4.
[0104] Carbon paper was acidified with concentrated nitric acid, sonicated with distilled water and anhydrous ethanol, and then 20 mg of prepared cerium cobalt phosphate catalyst, 713 μL of ethanol, 237 μL of water and 50 μL of nafion117 solution were mixed and sonicated until homogeneous, and then dropped onto the carbon paper to obtain the anode.
[0105] The reaction was carried out in a single electrolytic cell with a platinum sheet as the counter electrode, an Ag / AgCl electrode as the reference electrode, and carbon paper loaded with cerium cobalt phosphate as the anode. 0.05 mmol of p-methoxytoluene was added to 10 mL of 0.3 M mixed phosphate buffer. Before electrolysis, the cells were activated by CV for 15 cycles until stable, and then electrolysis was performed at 1.90 V vs. RHE.
[0106] Electrocatalytic tests were performed on A1-A4, and the results are shown in Table 2.
[0107] Table 2
[0108]
[0109] As shown in Table 2, the cerium cobalt phosphate catalyst provided by the present invention can effectively electrocatalytically oxidize toluene derivatives into biomass aldehydes.
[0110] The above description is merely a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.
Claims
1. A method for preparing a cerium cobalt phosphate catalyst, characterized in that, Includes the following steps: S1. Add H3PO4 solution dropwise into a mixed aqueous solution of cerium nitrate and cobalt nitrate, and stir to obtain a white, homogeneous gel-like solution; S2. Adjust the pH of the white, homogeneous gel-like solution to 5-9 using ammonia. S3. The solution after pH adjustment in S2 is subjected to a hydrothermal reaction, naturally cooled to 20-30℃, centrifuged, and the precipitate is washed with distilled water and ethanol, and then vacuum dried to obtain the cerium cobalt phosphate catalyst.
2. The preparation method according to claim 1, characterized in that, In step S1, the concentration of the H3PO4 solution is 0.1-1M; In a mixed aqueous solution of cerium nitrate and cobalt nitrate, Ce 3+ The concentration was 0.03-0.09 M, Co 2+ The concentration is 0.001-0.006M; H3PO4, Co 2+ and Ce 3+ The molar ratio is 1-2:0.03-0.1:
1.
3. The preparation method according to claim 1, characterized in that, In step S1, the stirring conditions include: stirring time of 1-2 hours and stirring frequency of 500-1000 RPM.
4. The preparation method according to claim 1, characterized in that, In step S2, the mass concentration of the ammonia water is 10-25%.
5. The preparation method according to claim 1, characterized in that, In step S3, the conditions for the hydrothermal reaction include: the temperature of the hydrothermal reaction is 100-140℃.
6. The preparation method according to claim 1, characterized in that, In step S3, the conditions for the hydrothermal reaction include: the hydrothermal reaction time is 8-24 h.
7. The preparation method according to claim 1, characterized in that, In step S3, the conditions for centrifugal separation include: a centrifugal speed of 8000-12000 r / min and a centrifugal separation time of 5-15 min.
8. The preparation method according to claim 1, characterized in that, In step S3, the conditions for vacuum drying include: a vacuum drying temperature of 50-80 ℃ and a vacuum drying time of 24-72 h.
9. The cerium cobalt phosphate catalyst prepared by the method according to any one of claims 1-8, characterized in that, The molar fraction of cobalt in the cerium cobalt phosphate catalyst is 3-10%.
10. The application of the cerium cobalt phosphate catalyst according to claim 9, characterized in that, The cerium cobalt phosphate catalyst electrocatalyzes the oxidation of biomass alcohols and toluene derivatives to biomass aldehydes, with a conversion rate of 98-99% and a selectivity of 80-92%.