74 results about "Palladium nanoparticles" patented technology

The invention discloses a Pd supported catalyst as well as a preparation method and application thereof, and belongs to the technical field of catalysts. The Pd supported catalyst is prepared according to the following steps: dissolving TEOS and MSDS in absolute ethyl alcohol, stirring, adjusting the pH value, aging at room temperature, and drying to obtain a mixture; and extruding the mixture into a long strip shape, calcining to prepare a TiO2-SiO2 composite carrier, dipping the TiO2-SiO2 composite carrier in a palladium nanoparticle solution, filtering, washing, and drying in vacuum to obtain the catalyst. The preparation method is simple and green in process, the reaction process is safe and easy to control, the prepared Pd supported catalyst is good in crystallization, high-dispersion nano-particle morphology, uniform in size and uniform in dispersion, and when the Pd supported catalyst is applied to co-production of methyl isobutyl ketone and methyl isoamyl ketone from mixed aldehyde and ketone, the isobutyraldehyde conversion rate can be effectively increased, and the yield of methyl isobutyl ketone and methyl isoamyl ketone can be effectively increased. The selectivity on methyl isoamyl ketone is good, and organic impurities in the product are few.

The invention belongs to the technical field of conductive materials, and particularly relates to a method for preparing and activating pyridine functionalized swelling polymer microspheres and a method for preparing core-shell structure polymer conductive microspheres. The preparation method comprises the following steps: by taking polystyrene microspheres as seeds, preparing pyridine functionalized polymer microspheres through an emulsion swelling method, then introducing Pd < 2 + > ions through coordination, preparing activated microspheres with palladium nanoparticles uniformly coated on the surfaces of the polymer microspheres through in-situ reduction, preparing nickel-plated microspheres with uniform metal coatings through chemical plating, and finally preparing the polymer microspheres with uniform metal coatings. And finally, preparing the core-shell structure gold-plated polymer conductive microspheres through in-situ reduction, and applying the core-shell structure gold-plated polymer conductive microspheres to preparation of anisotropic conductive films. Through an emulsion swelling method, not only can the polymer microspheres with adjustable sizes be prepared, but also the polymer microspheres with different morphologies can be prepared. The preparation method of the conductive microspheres has the advantages of being wide in raw material source, easy and convenient to operate and adjustable in metal coating thickness, and is suitable for high-precision packaging in the microelectronic industry.

The application provides a preparation method of a metal-functionalized graphene film, and belongs to the technical field of nanofluid mass transfer. The preparation method comprises the following steps: firstly, dispersing a palladium precursor and graphene oxide in an alcohol solvent, and growing palladium nanoparticles on the surface of the graphene oxide in situ through first heating to obtain a first dispersion liquid comprising graphene oxide loaded with the palladium nanoparticles; then adding deionized water and a reducing agent to the first dispersion liquid, stirring and performing second heating, so that the graphene oxide in the first dispersion liquid is reduced to reduced graphene oxide to obtain a second dispersion liquid comprising reduced graphene oxide loaded with the palladium nanoparticles; and finally, preparing a film from the second dispersion liquid to obtain the metal-functionalized graphene film. In other aspects of the application, a metal-functionalized graphene film obtained by the aforementioned preparation method and an application of the metal-functionalized graphene film in an electrically controlled ion separation device are also provided.

The application belongs to the technical field of wastewater treatment, and provides an electrochemical anode-cathode combined system, wherein a diaphragm divides an electrolytic cell into an anode chamber and a cathode chamber, the anode chamber is provided with a counter electrode and filled with activated carbon, the cathode chamber is provided with a working electrode and a reference electrode, the working electrode comprises a conductive base and a modified electroactive biofilm arranged on the surface of the conductive base, and the modified electroactive biofilm comprises an electroactive biofilm and palladium nanoparticles loaded on the electroactive biofilm.In the application, H* generated on the surface of the palladium nanoparticles on the electroactive biofilm can attack the carbon-halogen bond in PFASs, meanwhile, the electroactive biofilm can reduce nitrate by using electrode electrons, and then the activated carbon particles passing through the anode can be adsorbed and further purified and filtered, so that the electrochemical anode-cathode combined system provided by the application can effectively remove perfluoro / polyfluoroalkyl compounds and nitrate in wastewater at the same time.

The invention belongs to the technical field of nano-catalyst antibiosis, and particularly relates to a zinc-based nitrogen-doped carbon-loaded metal palladium nano-enzyme as well as a preparation method and application thereof. The ZnNC-loaded metal palladium nano-enzyme is prepared by adopting a deposition-precipitation method which is simple to operate, taking ZnNC as a carrier and taking metal palladium nano-particles as an active center. The nano-enzyme has excellent oxidase-like activity, can catalyze O2 to generate hydroxyl free radicals (. OH), singlet oxygen (< 1 > O2) and superoxide anion free radicals (O2 <->) so as to kill bacteria and achieve an antibacterial effect, and has a remarkable antibacterial effect on escherichia coli under an acidic condition.

The invention provides a palladium-based catalyst as well as a preparation method and application thereof. The palladium-based catalyst comprises a carrier and active components loaded on the carrier, the active components comprise metal Pd, metal Au and alkali metal acetate, the metal Pd contains Pd nano-particles with the average diameter being smaller than 5 nm, and the Pd nano-particles with the average diameter being smaller than 5 nm account for 1%-20% of the total weight of the metal Pd. The method for preparing the palladium-based catalyst comprises the following steps: (1) dipping a carrier loaded with metal Pd (0) and metal Au (0) in a nano-palladium dispersion liquid to obtain a catalyst precursor IV; and (2) dipping the catalyst precursor IV in a solution containing alkali metal acetate to obtain the palladium-based catalyst. The palladium-based catalyst provided by the invention has excellent catalytic activity and selectivity in a vinyl acetate preparation reaction.

This invention belongs to the field of catalyst materials technology, specifically relating to a Pd-UiO-66 particle electrode, its preparation method, and its application. The Pd-UiO-66 particle electrode uses a zirconium-based metal-organic framework UiO66 as a support. Palladium nanoparticles are obtained by reducing palladium salts with sodium borohydride. The palladium nanoparticles are then reacted with the hydroxyl groups on the polyvinyl alcohol molecules. 2+ The coordination between the components and the steric hindrance effect of the long-chain molecules of polyvinyl alcohol regulate the dispersion of palladium nanoparticles, allowing palladium nanoparticles to be loaded onto UiO66 to obtain Pd-UiO-66. The Pd-UiO-66 particle cathode in this invention avoids the aggregation of palladium nanoparticles, greatly increasing the electrode area / solution volume ratio and helping to provide more active sites for dechlorination.

This invention provides a hydrogen sensor based on nanoparticles, its preparation method, and its application, belonging to the field of hydrogen sensor technology. The nanoparticle-based hydrogen sensor provided by this invention includes a substrate and at least one pair of electrodes spaced apart on the surface of the substrate. The substrate surface between the electrodes is covered with nanoparticles, and the electrode surfaces and nanoparticle surfaces are covered with a thin film layer. The nanoparticles include one or more of palladium nanoparticles, platinum nanoparticles, and alloy nanoparticles, wherein the alloy nanoparticles contain palladium and / or platinum. The material of the thin film layer includes one or more of polymethyl methacrylate, naphthol, silica, alumina, polytetrafluoroethylene, diamond-like carbon film, silicon nitride, and silicon carbide. The nanoparticle-based hydrogen sensor provided by this invention has high sensitivity and excellent stability, enabling rapid and accurate determination of hydrogen in an air environment.

The invention relates to a nano MoS2 and PtPd combined BN / Au film sensor as well as a preparation method and application thereof, and belongs to the technical field of biosensors. According to the sensor, a glassy carbon electrode serves as a substrate, a boron nitride nanosheet, a gold film and a primary antibody are sequentially modified, a molybdenum disulfide composite material loaded with platinum-palladium nanoparticles and a secondary antibody are coupled to serve as a signal amplification probe, and thionine serves as an electron mediator. The preparation method comprises the steps of electrode pretreatment, BN / Au film modification, antibody fixation, nano composite probe preparation and the like. The sensor solves the problems that an existing detection method is complex in operation, depends on large-scale equipment and is difficult to meet POCT requirements, has the advantages of being high in sensitivity (the detection limit reaches 0.86 pg / mL), high in specificity, good in stability and suitable for rapid detection of serum samples, and provides an effective tool for early diagnosis of tumors.

A method for producing a nano-Pd catalyst supported on a nitrogen-doped hierarchical porous carbon, characterized in that it comprises: 1) Preparation of a nitrogen-doped hierarchical porous carbon, 2) Mixing the nitrogen-doped hierarchical porous carbon produced in step 1) with water and adjusting the pH of the mixed solution to alkaline. 3) Mixing the mixture solution prepared in step 2) with the aqueous solution of Pd metal precursors, adding reducing agent and obtaining the nano-Pd catalyst supported on the nitrogen-doped hierarchical porous carbon after reduction.

This invention relates to the field of trace gas leak detection, specifically to a highly sensitive and fast-response hydrogen sensor based on palladium single-atom doping, its preparation method, and its application. The method includes the following steps: preparing indium hydroxide material using indium ions, anhydrous ethanol, ammonia, and deionized water; then doping palladium ions into the indium hydroxide solution to obtain a palladium ion-doped indium hydroxide solution; reducing the solution with sodium borohydride; centrifuging to obtain palladium cluster-doped indium hydroxide material; subsequently calcining the palladium cluster-doped indium hydroxide composite material at high temperature to obtain a palladium single-atom-doped indium oxide composite material; and finally transferring the palladium single-atom-doped indium oxide onto an electrode substrate surface to obtain the hydrogen sensor. This invention, through improvements to key processes, effectively solves the problems of poor selectivity in pure indium oxide gas sensors and slow response speed in palladium nanoparticle-doped hydrogen sensors, achieving rapid and highly sensitive trace detection of hydrogen.

The invention belongs to the technical field of catalysis, and discloses an oxide-nitrogen-containing intrinsic microporous polymer nano composite carrier supported palladium catalyst as well as a preparation method and application thereof. The catalyst takes an inorganic nano oxide as a matrix, nitrogen-containing intrinsic microporous macromolecules are deposited on the surface of the matrix to form a composite carrier with a dual-distribution pore structure, the inorganic oxide provides macropores, and the macromolecules provide micropores; the nitrogen-containing intrinsic microporous polymer contains a tertiary amine structural unit, and nitrogen atoms of the tertiary amine structural unit are coordinated with palladium nanoparticles, so that anchoring and high dispersion of palladium are realized. The preparation method of the catalyst comprises the following steps: firstly synthesizing a nitrogen-containing intrinsic microporous polymer, then compounding the nitrogen-containing intrinsic microporous polymer with an oxide to prepare a carrier, and finally loading a palladium precursor and performing hydrogen reduction. The catalyst shows high conversion rate, high selectivity and excellent cycle stability in styrene oxide hydrogenation, acrylonitrile hydrogenation and phenylacetylene hydrogenation reactions, the preparation process is simple and convenient, and the catalyst has a good industrial application prospect.

The application provides a resource treatment method of waste palladium catalyst. The method first carries out microwave carbon removal, plasma etching and N-TiO2 light catalyst loading on the waste palladium catalyst to complete carrier loosening modification; then in a supercritical extraction kettle with an embedded ultraviolet LED lamp, a gradient strategy of 'weak complexing agent pre-washing impurity removal + strong complexing agent main palladium extraction' is adopted, combined with light catalysis-super critical synergistic effect to strengthen palladium desorption and selective extraction; then the impurity metal and weak complexing agent are recovered through reduced pressure condensation, and the palladium complex fluid is purified through a silica gel adsorption column; then the purified fluid is introduced into a loading kettle to mix with a carrier precursor suspension, hydrogen is introduced for in-situ reduction, and palladium nanoparticles are loaded, and a palladium-based catalyst applicable to industrial application is directly obtained through drying and calcination; finally, the waste carrier is microwave activated (active carbon carrier is additionally steam activated) to realize deep reuse.

The invention relates to the technical field of immunosensors, in particular to a CeO2-Pd NPs composite material, an immunosensor, a preparation method and application. The preparation method of the CeO2-Pd NPs composite material comprises the following steps: dissolving cerium salt and a polyvinylpyrrolidone solution in an organic solvent, adding an inorganic solvent, and carrying out a second heating reaction to obtain cerium dioxide; dissolving potassium salt, L-ascorbic acid and polyvinylpyrrolidone in an inorganic solvent, carrying out a third heating reaction, adding a palladium salt solution, and continuing the third heating reaction to obtain Pd NPs, namely palladium nanoparticles; the preparation method comprises the following steps: dispersing cerium dioxide in an inorganic solvent, and adding Pd NPs to obtain a CeO2-Pd NPs composite material; the invention also provides the CeO2-Pd NPs composite material prepared by the method, an immunosensor and a preparation method. The problem that an existing sensor is low in sensitivity when used for detecting DBP is solved.

The invention provides a preparation method of a foam metal composite hydrogen storage material, which comprises the following steps: mixing vanadium-containing alloy powder, a pore-forming agent and an organic binder, carrying out compression molding, and carrying out heat treatment to densify the alloy so as to obtain an inner-layer pressure-bearing framework; depositing a magnesium-titanium nano composite layer through a magnetron co-sputtering technology; growing a graphene layer through chemical vapor deposition; immersing the framework on which the graphene layer grows into a solution containing palladium salt, and generating and loading palladium nanoparticles on the surface of graphene in situ to form a surface catalyst layer, so as to obtain a metal foam framework; and immersing in a solution containing zircon salt and an organic ligand, and growing a metal organic framework on the surface in situ through solvothermal reaction to obtain the foam metal composite hydrogen storage material. The mechanical strength, the hydrogen storage capacity and the dynamic performance of the material are improved, the stability of the material in hydrogen absorption and desorption circulation is improved, and the defects of a traditional hydrogen storage material in the aspects of mechanical performance, hydrogen storage efficiency, circulation stability and the like are overcome.

This invention discloses a palladium-based catalyst for the semi-hydrogenation of alkynols to enols and its preparation method. Specifically, a metal salt is added to deionized water and ultrasonically dispersed to obtain a uniformly dispersed metal salt solution. A support powder is uniformly spread on a polytetrafluoroethylene plate. The metal salt solution is loaded into a syringe pump and slowly added dropwise onto the support. The solution is allowed to stand and age to obtain a wet support. The wet support is transferred to an oven for calcination. The calcined sample is transferred to a tube furnace for reduction to obtain the palladium-based catalyst. The palladium-based catalyst of this invention can be applied to the selective hydrogenation reaction of alkynols. By controlling the impregnation rate, the active precursor solution is ensured to be absorbed instantaneously and completely, and the enrichment of the active component at the edges is effectively suppressed. High-temperature reduction achieves partial encapsulation of palladium nanoparticles with indium oxide, thereby altering their electronic structure and improving the selectivity for the semi-hydrogenation of alkynols to enols.

This invention relates to the field of hydrogen detection technology, and in particular to a low-concentration hydrogen detector and detection method based on a nano-palladium-nickel alloy, which can achieve high sensitivity and rapid response for detecting low-concentration hydrogen at room temperature. The detector includes: a nano-sensitive chip module with a palladium-nickel alloy-based nano-sensitive thin film, wherein the nano-sensitive thin film has a suspended micro / nano waveguide structure, and hydrogen is adsorbed and converted into a resistance change signal based on the surface scattering effect of the suspended micro / nano waveguide structure; a signal modulation circuit electrically connected to the nano-sensitive chip module, used to convert the resistance change signal into a differential voltage signal; and an intelligent calculation module electrically connected to the signal modulation circuit, used to perform inversion calculation on the differential voltage signal and output the hydrogen concentration value.

The invention relates to the technical field of gas sensors, in particular to a hydrogen sensor for lithium battery safety monitoring and a sensitive material preparation method, and aims at solving the problems that an existing hydrogen sensitive material is low in recovery speed and insufficient in sensitivity. Tungsten trioxide is adopted as a matrix of the sensitive material, compared with common materials such as tin oxide and zinc oxide, the sensitive material has the response characteristic of being more sensitive to hydrogen, the intrinsic sensitivity and the reaction rate of the material to hydrogen are improved through the synergistic dual sensitization effect of K + bulk phase doping and palladium nanoparticle surface catalysis, and the sensitivity of the material to hydrogen is improved. A sacrificial template is introduced into a tungsten trioxide sensitive layer prepared by aerosol deposition, and a segmented annealing process is adopted, so that a controllable porous structure is constructed while sufficient removal of the template and film continuity are ensured, and the sensitivity and response / recovery performance of the hydrogen sensor are improved; the sensor is suitable for lithium ion battery thermal runaway safety monitoring scenes with extremely harsh early warning requirements.

The application belongs to the field of photoelectrocatalysis, and relates to a non-biased hydrogen peroxide and C3 chemical co-production device based on a Pd-CuO / W-CuBi2O4 photo-cathode and application thereof. The application constructs a heterojunction photo-cathode composed of CuO and tungsten-doped CuBi2O4, and modifies palladium nanoparticles (Pd:CuO / W-CBO) for efficient and stable photoelectrochemical hydrogen peroxide generation. A non-biased photoelectrochemical system is constructed, which uses a Pd:CuO / W-CBO photo-cathode and a Pt / TiO2 anode to realize the synchronization of solar-driven hydrogen peroxide production and electrochemical glycerol oxidation to generate high-value chemicals. The hydrogen peroxide generated at the cathode can realize rapid water disinfection, and the work shows an expandable photoelectrochemical platform capable of stably generating solar-driven hydrogen peroxide and glycerol value-added at the same time, while generating renewable electricity.

The invention provides a method for repairing negative electrode graphite for a waste lithium ion battery. The method comprises the following steps: putting the negative electrode graphite for the waste lithium ion battery into a chemical vapor deposition furnace, introducing an organic carbon source gas, and carrying out chemical vapor deposition to prepare repaired graphite 1; the repaired graphite 1, water and a palladium precursor are mixed for adsorption, after adsorption is finished, a reducing agent is added into a reaction system for a reduction reaction, and a nano-palladium / repaired graphite 1 composite material is prepared; putting the nano-palladium / repaired graphite 1 composite material into a high-temperature furnace, introducing acetylene, and carrying out polymerization reaction to prepare repaired graphite 2; the repaired graphite 2 is subjected to graphitization treatment, and repaired graphite 3 is prepared; mixing the repaired graphite 3 with asphalt, and carrying out carbonization treatment; according to the method, the interior and the surface of the negative electrode graphite for the waste lithium ion battery can be synchronously repaired, and the negative electrode graphite material with good cycle performance can be obtained.

The present application relates to a kind of visible light catalytic adjacent wood reaction palladium / perovskite material and preparation method and application.The present application belongs to the cross field of inorganic chemistry, organic chemistry, material chemistry.The palladium / perovskite material prepared in the present application has the chemical formula Pd / CsPbBr3, wherein the particle size of CsPbBr3 is 40-300nm, the size of palladium nanoparticle is 2-5nm, the visible light absorption range of palladium / perovskite material for visible light catalytic adjacent wood reaction can be extended to 532nm, photo-generated charge is generated by visible light excitation, and visible light catalytic suzuki reaction is carried out, to produce a series of biphenyl compounds connected with different substituents.The method of the present application is simple to operate, cost-saving, and mild reaction conditions, which has important significance in the field of visible light catalytic suzuki reaction technology.

The invention discloses an amino resin loaded nano-palladium composite functional material as well as a preparation method and application thereof, a matrix of the composite functional material is chloromethylated polystyrene resin grafted with a polyamine group compound, the crosslinking degree of the chloromethylated polystyrene resin is 4-8%, the particle size is 0.30-0.90 mm, the pore diameter is 1-50 nm, and the nano-palladium loaded nano-palladium composite functional material is prepared from the amino resin loaded nano-palladium composite functional material. The polyamine group compound is a compound comprising two primary amine groups and at least one secondary amine group; pore structures are uniformly distributed on the surface of the substrate, and nano-palladium particles are loaded in pores; and the loading rate of the nano-palladium particles in the composite material is 0.25%-5% in percentage by mass. The invention develops a novel functional material which is efficient and stable and has adsorption enrichment and targeted reduction capacities, the efficient removal efficiency of the Cu-organic complex and the in-situ recovery of the copper element are realized, and the treatment of water pollution and the resource recovery of the copper element are cleanly and effectively realized.

The invention belongs to the technical field of metal materials, and discloses a preparation method of palladium powder for high-palladium silver paste, which comprises the following steps: dissolving PdCl2 in diluted hydrochloric acid to form H2PdCl4 solution, and regulating the pH value to 8-9.5 by NaOH; adding polyvinylpyrrolidone (PVP) as a dispersing agent, slowly dropwise adding a sodium formate solution under the assistance of ultrasonic waves, and carrying out mild reduction at the reaction temperature of 60-80 DEG C, so as to prepare a palladium nanoparticle suspension; after centrifugal washing, vacuum drying and screening, a stearic acid ethanol solution is adopted to modify the surface of the palladium powder, and the compatibility of the palladium powder and an organic carrier is improved. The adhesive force shedding rate of the high-palladium silver paste prepared from the palladium powder prepared by the preparation method disclosed by the invention is as low as 1.35%-3.13%, the sheet resistance is 13.1-15.8 m omega, and the high-palladium silver paste is obviously superior to that of a traditional method, and is suitable for 5G communication, MLCC and other high-end electronic devices.

The invention discloses a difunctional nanoparticle and a construction method thereof in the technical field of biosensors. The nanoparticle comprises a ferroferric oxide magnetic core, a mesoporous silicon dioxide shell layer coated on the surface of the magnetic core, palladium nanoparticles modified on the surface of the silicon dioxide shell layer, and luminol molecules coupled to the silicon dioxide shell layer through covalent bonds. The material has superparamagnetism, a high specific surface area, a mesoporous structure and efficient peroxide activity, can accelerate hydrogen peroxide to generate hydroxyl radicals (OH), and can promote luminol to generate strong electrochemiluminescence signals. The superparamagnetism can be used as a trapping agent for trapping exosomes in body fluid. The PD-L1-modified gold electrode is combined with the exosome-nanoparticle compound, so that the PD-L1 exosome can be sensitively and quickly detected, and the PD-L1-modified gold electrode has important significance in early discovery of non-small cell lung cancer and prediction of the treatment effect of an immune checkpoint inhibitor.

The application provides a hydrogen-sensitive material and a preparation method thereof, a hydrogen-sensitive sensor and a preparation method and application thereof, and belongs to the technical field of hydrogen-sensitive materials. The hydrogen-sensitive material comprises a Ti3C2 / TiO2 heterojunction and palladium nanoparticles loaded on the surface of the Ti3C2 / TiO2 heterojunction. The application adopts the Ti3C2 / TiO2 heterojunction to load the palladium nanoparticles to form a three-phase heterojunction, so that the transmission of charges is accelerated, the sensitivity and response speed are greatly improved under the excitation of ultraviolet and infrared light, and the hydrogen-sensitive sensor can respond to hydrogen at room temperature. The results of the examples show that the hydrogen-sensitive sensor prepared from the hydrogen-sensitive material provided by the application has a hydrogen sensitivity of 69.9% at room temperature, and a response time of 16s.

The invention relates to the technical field of electrode catalysts, in particular to a palladium / cerium oxide nanorod / reduced graphene oxide three-dimensional composite electrode catalyst and a preparation method and application thereof.The preparation method comprises the steps that firstly, a cerium oxide nanorod is prepared, then the prepared cerium oxide nanorod is placed in ethylene glycol, a graphene solution is added, ultrasonic mixing is conducted, and then the palladium / cerium oxide nanorod / reduced graphene oxide three-dimensional composite electrode catalyst is obtained. The preparation method comprises the following steps: adding a cerium oxide nanorod into reduced graphene oxide, adding a palladium salt solution, uniformly stirring, carrying out a solvothermal reaction to form a hydrogel-like product, carrying out dialysis washing on the product, and carrying out freeze drying treatment to finally prepare the palladium / cerium oxide nanorod / reduced graphene oxide three-dimensional composite electrode catalyst. The prepared composite electrode catalyst has a relatively large specific surface area, an optimized electronic structure, sufficient electron transmission channels and uniform distribution of palladium nanoparticles, and the characteristics have remarkable advantages on formic acid and methanol oxidation reactions, and can be applied to the field of catalysis of direct liquid fuel batteries.

The invention belongs to the technical field of catalyst preparation, and particularly relates to an efficient anthraquinone hydrogenation catalyst and a preparation method thereof. The preparation method comprises the following steps: (1) modifying aluminum oxide by adopting a long straight carbon chain alkyl silane coupling agent to obtain a primary modified aluminum oxide carrier; (2) modifying the primary modified alumina carrier again by using an amino-containing silane coupling agent to obtain a modified alumina carrier; and (3) impregnating the modified alumina carrier with a palladium salt-containing solution, and then carrying out drying, roasting and hydrogen reduction to obtain the efficient anthraquinone hydrogenation catalyst. Firstly, a small amount of alkyl silane coupling agent with a long straight carbon chain is used for modifying an aluminum oxide carrier, so that not only can the morphology of the aluminum oxide carrier be prevented from being damaged, but also the alkyl silane coupling agent can be uniformly dispersed on the surface of the aluminum oxide carrier, and agglomeration of the amino-containing silane coupling agent in the modification process of a large amount of amino-containing silane coupling agent is prevented; the palladium nanoparticles can be dispersed more uniformly, so that the catalyst has higher catalytic activity.

This invention discloses a carbon nitride-supported noble metal catalyst, its preparation method, and its application, belonging to the technical field of preparation and application of supported noble metal catalysts. Using melamine as a precursor, graphitic carbon nitride (g-C3N4) support is obtained through high-temperature calcination and ultrasonic exfoliation. Noble metal palladium nanoparticles are then loaded onto the surface of g-C3N4 via an impregnation-reduction method to obtain a Pd / g-C3N4 catalyst. In the prepared catalyst, palladium nanoparticles are uniformly dispersed on the support surface, with an average particle size of approximately 3.2 nm, and the mesoporous structure of the support remains intact before and after loading. This invention features a simple preparation method, low noble metal usage, and high catalyst activity, exhibiting excellent catalytic performance in the hydrogenation of 5-hydroxymethylfurfural to 2,5-dimethylfuran. Under reaction conditions of 150 °C, 1.5 MPa H2, and formic acid as the hydrogen donor, a 1% Pd / g-C3N4 catalyst can achieve complete HMF conversion, with a DMF selectivity of 95% and a conversion frequency of 362 h⁻¹. ‑1 Even after five cycles of use, it still maintains a conversion rate of 93% and a selectivity of 83%, showing good prospects for industrial application.

The invention discloses a preparation method and application of a nitrogen-doped carbon nanomaterial of hydrophobic carbon dot barrier induced highly-dispersed palladium nanoparticles, hydrophobic carbon dots are used as a dispersant, and a highly-dispersed Pd / hy-CDs (at) NCNS catalyst is prepared on a nitrogen-doped carbon nanosheet (NCNS) carrier and is used for nitrobenzene hydrogenation reaction. According to the invention, controllable loading and precise size regulation and control of palladium particles are realized. Under mild conditions, the catalyst can achieve 99.5% of nitrobenzene conversion rate within 4 hours. The strategy effectively enhances the dispersity of the precious metal, inhibits the agglomeration phenomenon and improves the catalytic stability.