85 results about "Pd nanoparticles" patented technology

The invention provides a Cu2O-based heterogeneous composite material as well as a preparation method and application thereof. The preparation method comprises the following steps: coating the surface of a Cu2O hollow sphere substrate with a carbon layer, and depositing layered double hydroxides (LDHs) and metal palladium (Pd) nanoparticles on the carbon layer. According to the material, through a Cu2O-carbon layer-LDHs-Pd multistage heterostructure design, space optimization of light absorption, charge transfer and catalytic sites is realized; cu2O-carbon layer-LDHs interface coupling promotes directed migration of photo-induced electron-hole pairs, and the surface plasmon resonance effect of Pd nanoparticles enhances the charge separation efficiency; the LDHs optimizes a charge transfer path through surface oxygen vacancy or metal valence cycle, so that synergistic oxidation of non-free radicals and free radicals is realized, the organic matter degradation efficiency is remarkably improved, the oxidation path is widened, and the performance bottleneck of a single material is broken through.

The invention discloses a catalyst for catalyzing ethane to prepare ethylene or an oxygen-containing compound as well as a preparation method and application of the catalyst, and belongs to the field of catalysts. On the basis of ERB-1 and MCM-22, a large number of hydroxyl structures are formed through post-treatment of nitric acid or ammonium nitrate; a titanium source and molecular sieve silicon hydroxyl are subjected to a dehydrohalogenation reaction in a titanium halide gas form to form a Ti-O-Si bond, so that titanium successfully enters a molecular sieve framework and is uniformly distributed. Au or Pd is anchored by a framework Ti, Au or Pd is loaded by using a deposition-precipitation method, and the introduced Ti species can provide a better environment for further dispersing Au or Pd by changing isoelectric points on the surface of a molecular sieve carrier, so that the size of Au or Pd nanoparticles is controlled; secondly, due to the high specific surface area of the MWW molecular sieve, the gold precursor can be effectively dispersed, and agglomeration is inhibited; compared with an MWW molecular sieve of pure Si, Au or Pd nanoparticles can be dispersed and anchored by introducing a framework Ti, so that an Au and Pd-based catalyst which is about 2nm in size and good in dispersion is prepared.

This invention discloses a method for modifying the support medium of a Pd catalyst and its application. The preparation method of the Pd catalyst includes reacting zirconium salt, organic ligands, and acid to obtain a support UiO-66-X; then loading Pd onto the support UiO-66-X and reducing it to obtain the catalyst Pd@UiO-66-X; the organic ligands include 2-nitroterephthalic acid, 2-methoxyterephthalic acid, 2-aminoterephthalic acid, and terephthalic acid, and X is selected from NO2, OMe, NH2, and H. This invention changes the surface electron cloud density of the supported Pd nanoparticles by changing the ligands (-NO2, -H, -OMe, -NH2) of the support UiO-66, resulting in different abilities to activate hydrogen, thereby regulating the dehydrogenation and hydrogenation reactions in the racemicization process of Pd catalysis. The synergistic effect of different ligands with Pd changes the racemicization catalytic activity.

A general method for synthesizing a series of novel amorphous-crystalline palladium (Pd) -based heterophase nanocatalysts for various promising electrocatalytic applications. The synthesized amorphous-crystalline Pd-PdAu core-island nanocatalyst exhibits high activity, fast reaction kinetics, and excellent long-term catalytic stability toward glycerol oxidation reaction (GOR). Remarkably, the main product of glycerol catalyzed by amorphous-crystalline Pd-PdAu core-island heterostructure is glyceric acid, which possesses the highest commercial value among all the GOR products. The one-pot synthesized amorphous-crystalline Pd-PdPt Janus heterostructure shows remarkable catalytic activity, and fast reaction kinetics towards formic acid oxidation reaction (FOR) in alkaline solution in comparison with commercial Pt / C catalyst and amorphous Pd nanoparticles (NPs), which benefits the development of advanced electrocatalysts for practical applications. The synthesized amorphous-crystalline PdCu Janus heterostructures with bcc phase exhibit high activity, fast reaction kinetics, and excellent long-term catalytic stability for hydrogen evolution reaction (HER) and 5-hydroxymethylfurfural oxidation reaction (HMFOR), benefiting the development of advanced electrocatalysts for practical applications.

The invention discloses a Pd-coated S-COF catalyst for a reaction of preparing styrene through phenylacetylene hydrogenation as well as preparation and application of the Pd-coated S-COF catalyst. The Pd (at) S-COF catalyst comprises a covalent organic framework carrier S-COF and Pd nanoparticles, the covalent organic framework carrier S-COF is an imine bonded covalent organic framework prepared by using 2, 4, 6-tri (4-aminophenyl)-1, 3, 5-triazine and 2, 5-dimethyl thioether-1, 4-phthalaldehyde as raw materials, and the Pd nanoparticles are used for modifying Pd nanoparticles. The Pd nano-particles are encapsulated in pore channels of the S-COF and are loaded on the surface of the S-COF. The invention provides an application of the Pd-coated S-COF catalyst in a reaction for preparing styrene through phenylacetylene hydrogenation, and high phenylacetylene conversion rate and high styrene selectivity can be realized within a short reaction time.

The invention discloses a Pd-SnO2-SiO2 self-supporting flexible nanofiber membrane gas sensor for hydrogen detection and a preparation method of the Pd-SnO2-SiO2 self-supporting flexible nanofiber membrane gas sensor, and aims to solve the problems that an existing flexible gas sensor depends on an organic substrate and is poor in high temperature resistance and insufficient in room temperature performance. According to the sensor, an electrostatic spinning technology is adopted for preparing a double-phase nanofiber membrane with crystalline phase SnO2 as a framework and amorphous phase SiO2 as a filling agent, and self-supporting can be achieved without a flexible substrate; pd nanoparticles are deposited on the fiber membrane through magnetron sputtering, and an Ag interdigital electrode is printed. Wherein the crystal-amorphous double-phase structure not only endows the material with excellent flexibility and high air permeability, but also provides a rich gas reaction interface; due to the full-inorganic characteristic, the high-temperature-resistant performance is achieved. The sensor shows high sensitivity, high selectivity and good flexible stability to hydrogen at room temperature under the environment of 37 DEG C and 80% humidity, is suitable for detecting hydrogen exhaled by a human body through wearable equipment such as a mask, and provides a new scheme for the metal oxide flexible gas sensor.

The invention discloses a TiO2 photocatalyst co-modified by Ni monatomic and Pd nanoparticles, a preparation method of the TiO2 photocatalyst and application of the TiO2 photocatalyst in preparation of olefin through photocatalysis of non-oxidative dehydrogenation of alkane. The preparation method comprises the following steps: firstly, preparing a monatomic photocatalyst with an organic ligand by using a surface organometallic chemical method, then calcining to obtain the monatomic photocatalyst, and then combining with a photodeposition method to prepare the photocatalyst simultaneously containing monatomic and nanoparticles. The Ni single atom in the obtained photocatalyst can enable the adjacent Pd nanoparticles to selectively photocatalyze alkane dehydrogenation to prepare olefin, so that the photocatalyst has excellent dehydrogenation activity, higher product selectivity and carbon deposition resistance in photocatalyze alkane non-oxidative dehydrogenation to prepare olefin.

The invention provides a catalyst as well as a preparation method and application thereof and a preparation method of tetrahydrofurfuryl alcohol, the catalyst takes mesoporous silica as a carrier, the surface of the carrier is modified with polyethylene glycol and an alkyl chain to form an amphiphilic surface, and Pd nanoparticles are loaded in mesopores. The surface of the mesoporous silica supported palladium catalyst is modified with polyethylene glycol and alkyl chains through covalent bonds to form an amphiphilic interface, hydrophilic polyethylene glycol chains enrich furfuryl alcohol molecules through hydrogen bonds, and hydrophobic alkyl chains capture hydrogen microbubbles, so that the gas-liquid interfacial tension can be effectively reduced, large bubbles can be broken, and nano bubbles can stably exist; and the preparation of tetrahydrofurfuryl alcohol realizes efficient reaction under obviously reduced pressure.

The invention discloses a preparation method of a difunctional Pd catalyst co-modified by a hydrophobic anionic ionic liquid and NOH and application of the difunctional Pd catalyst in direct synthesis of H2O2. According to the catalyst, a porous material is used as a matrix, a NOH layer which provides rich hydroxyl groups and amino groups and has adhesion is used as a first modified layer, anion ionic liquid (IL-Cl) is used as a second modified layer, and chloropalladate radicals PdCl4 < 2-> are chemically grafted on the first modified layer and the second modified layer and are reduced into Pd nano particles in situ, so that the Pd nano particles are obtained. And finally, carrying out ion exchange with anion Cl <-> on the ionic liquid to introduce hydrophobic anions on the catalyst to obtain the difunctional Pd catalyst. The difunctional Pd catalyst provided by the invention has high catalytic activity, high H2O2 selectivity and high yield, and also has good stability.

The invention provides a preparation method of a high-selectivity semi-hydrogenation MOF (Metal Organic Framework) supported palladium catalyst for catalyzing acetylene. According to the invention, 2-methylimidazole is used as a ligand, Zn < 2 + > is used as a metal node, water is used as a solvent, and a ZIF-8-dia carrier is synthesized at room temperature by controlling the molar ratio of Zn < 2 + > to 2-methylimidazole; and depositing Pd < 2 + > on the ZIF-8-dia carrier by using a reducing agent to synthesize the MOF supported palladium catalyst. Strong electron interaction is formed between Pd nano-particles and a carrier loaded in the MOF loaded palladium catalyst, a rich Pd-N structure is constructed on the interface of the Pd nano-particles and the carrier, formation of Pd0 species is inhibited, the hydrogen activation capacity of the Pd nano-particles is reduced, excessive hydrogenation of acetylene is inhibited, and therefore the selectivity of ethylene is improved; the catalyst shows excellent catalytic performance in acetylene hydrogenation reaction, at 160 DEG C, the acetylene conversion rate reaches 100%, the ethylene selectivity is 85%, and the catalyst has excellent durability and stability.

The invention relates to the technical field of catalysts, in particular to a palladium-based catalyst derived from MOFs as well as a preparation method and application of the palladium-based catalyst. The preparation method comprises the following steps: firstly preparing an MOF material, then preparing a palladium-based MOF precursor, mixing the palladium-based MOF precursor with a nitrogen-containing precursor, heating and roasting in an inert atmosphere, and cooling to room temperature. An external nitrogen-containing precursor is introduced in the high-temperature pyrolysis process and is jointly roasted with a palladium-based MOF precursor, the nitrogen doping amount in the carbon carrier is remarkably increased, and high dispersion and electronic structure optimization of Pd particles are achieved by enhancing the anchoring effect and electronic regulation and control of nitrogen species on the Pd nanoparticles; therefore, high activity, high selectivity and high stability are simultaneously obtained in the selective hydrogenation reaction of 2-methyl-3-butyne-2-alcohol.

The application is suitable for the technical field of nanometer material synthesis and application, and provides a preparation method of crystalline PdCN@amorphous PdP core-shell nanoparticles, which comprises the following steps: polyvinylpyrrolidone, L-ascorbic acid and potassium bromide are added into deionized water to form a mixed solution, after preheating of an oil bath, sodium chloropalladate solution is injected, and then transferred to the oil bath for reaction, and after centrifugation and cleaning, cubic Pd nanoparticles are obtained; the cubic Pd nanoparticles are dissolved in dimethyl sulfoxide solution, transferred to a reaction kettle for reaction, and after centrifugation and cleaning, cubic PdCN nanoparticles are obtained; the cubic PdCN nanoparticles are mixed with oleylamine solution, and after adding trioctylphosphine solution and heating, centrifugation and cleaning, the crystalline PdCN@amorphous PdP core-shell nanoparticles are successfully obtained. The reagents used in the application can be purchased on the market and do not need further treatment, the preparation method is simple, and the required equipment is all basic laboratory equipment, without expensive equipment and instruments.

The invention provides a nano array for exposing a SnO2 high-activity crystal face, a preparation method of the nano array and application of the nano array in hydrogen sensing. The preparation method of the Pd-SnO2 nanowire array comprises the following steps: (1) synthesizing a SnO2 nano array on the surface of a substrate; and (2) loading the Pd nano particles on the SnO2 nano array, so as to obtain the Pd-SnO2 nanowire array. The palladium nanoparticle-loaded SnO2 nanowire array can rapidly and sensitively detect hydrogen under a low-temperature condition, has excellent sensitivity, shows excellent selectivity and reliable stability, has a detection lower limit reaching a ppm level, and is high in response speed and good in reproducibility. When the palladium nanoparticle loaded SnO2 nanowire array is used for preparing a hydrogen sensing device, the energy consumption is reduced, and the hydrogen sensing device is safer and more environment-friendly.

The invention belongs to the technical field of biomedicine, and discloses a magnetic bead aptamer sensor based on MnTiO3atPd nanoparticle colorimetry, a construction method and application. The preparation method comprises the following steps: synthesizing a MnTiO3 nanodisk by using a one-step hydrothermal method, and further synthesizing MnTiO3 (at) Pd nanoparticles; designing a capture probe and a signal probe according to the nucleotide sequence of the endotoxin aptamer; synthesis of a capture probe: a magnetic bead modified aminated nucleotide single strand; the method comprises the following steps: synthesizing a signal probe by utilizing ssDNA and MnTiO3 (at) Pd nanoparticles; and constructing the colorimetric aptamer sensor by using the capture probe and the signal probe. The magnetic bead aptamer sensor based on MnTiO3 at Pd nanoparticle colorimetry provided by the invention is used for detecting endotoxin in plasma. The aptamer sensor designed by the invention provides a low-cost, high-sensitivity and rapid method for detecting endotoxin, and quantitative and qualitative detection can be simultaneously carried out.

The invention discloses a Pd / (HfNb series) C / TaZr composite film, Pd is loaded on the surface of the (HfNb series) C / TaZr composite film in the form of nanoparticles, the Pd nanoparticles are 5-50 nm, (HfNb series) C is obtained by carbonizing a high-entropy film formed by mixing HfNb with one or more than two of Ti, Ta and Zr, the thickness of the (HfNb series) C is 0.05-0.15 [mu] m, and the mass percentage content of Zr in TaZr is 0.5-8%; the preparation method of the composite film comprises the following steps: 1, smelting; 2, processing a TaZr foil sheet; 3, preparing a film layer on the surface of the TaZr foil and carbonizing; 4, Pd nano particles are deposited; and 5, annealing. By introducing the (HfNb system) C film layer on the surface of the TaZr film, mutual diffusion at the interface of the composite film layer is inhibited, degradation and failure of the hydrogen permeation performance of the composite film are avoided, the stability of the composite film in the hydrogen permeation process is improved, and the method is suitable for the field of hydrogen purification.

The application provides a Pd-Cu bimetallic supported In2O3-TiO2 catalyst and a preparation method and application thereof, and belongs to the technical field of CO2 hydrogenation to prepare methanol. The catalyst comprises a composite carrier and Pd nanoparticles and Cu nanoparticles supported on the surface of the composite carrier. Pd and Cu are combined to form bimetallic sites in the application, the advantages of the bimetallic sites can be fully exerted, and the reaction activity of CO2 hydrogenation to prepare methanol can be significantly improved through the electronic effect and geometric effect between the metals. The Pd-Cu / In2O3-TiO2 catalyst provided by the application has the advantages of high conversion rate and high catalytic activity in the reaction of carbon dioxide hydrogenation to prepare methanol; wherein, in the process of carbon dioxide hydrogenation, the Pd-Cu / In2O3-TiO2 catalyst can obtain a one-way CO2 conversion rate of 23.5% and a methanol yield of 15.83% at 250 DEG C.

The invention discloses a preparation and application of a Pd nanoparticle modified hydrogen production photocatalytic material, and relates to the field of catalysts. A UiO-66-NH2 material is prepared by a hydrothermal method, and a semiconductor material cerium trisulfide is loaded on the surface of the UiO-66-NH2 by a precipitation method. An oxygen vacancy defect is introduced on the surface of a Ce2S3 / UiO-66-NH2 heterostructure by a chemical reduction method as a photogenerated electron capture center. Pd nanoparticles are induced and anchored on the material surface by combining a photodeposition method, and finally a highly dispersed Pd nanoparticle modified hydrogen production photocatalytic material is prepared. The introduction of oxygen vacancies in the composite material and the surface plasma resonance effect of the Pd nanoparticles can effectively improve the light absorption capacity, and the built-in electric field formed in the heterostructure of the composite material can drive the directional movement of photogenerated charges and reduce the recombination rate of photogenerated charges. The synergistic effect of the two can enhance the photocatalytic hydrogen production efficiency of the composite material.

The invention discloses a preparation method and application of a nitrogen-doped carbon nanotube modified Beta zeolite loaded PdNi bimetallic catalyst of dodecahydro-N-ethyl carbazole, and aims to solve the problems of high dehydrogenation temperature, low rate and the like in the application of 12H-NEC catalytic dehydrogenation. The preparation method comprises the following steps: 1, adding Beta zeolite into a nickel salt aqueous solution, dipping to obtain a Ni / Beta catalyst, mixing melamine and the Ni / Beta catalyst, putting the mixture into a tubular furnace, and carrying out a carbon thermal reduction reaction at the temperature of 500-900 DEG C in an N2 atmosphere; and 2, adding the Ni / Beta-NCNT into a solution of a palladium precursor, and carrying out an electric replacement reduction reaction. The introduction of the NCNT improves the electron transport capacity, defect sites formed on the surface of the CNT after N doping promote dispersion of Pd nanoparticles, and the synergistic effect of the two effectively improves the catalytic performance of the Pd nanoparticles in the dehydrogenation reaction of dodecahydro-N-ethyl carbazole.

The invention provides an alkaline modified UiO-66 supported Pd nano-catalyst as well as a preparation method and application thereof, and relates to the technical field of catalysts. According to the catalyst, UiO-66 serves as a precursor, isonicotinic acid is used for substitution modification through a solvent-assisted ligand exchange strategy, then Pd nanoparticles are loaded through a co-reduction method to form the corresponding composite catalyst Pd / UiO-66-PA, and the catalyst is a regular octahedral porous composite material; the invention further provides application of the alkaline modified UiO-66 loaded Pd nano-catalyst in efficient hydrogen generation through formic acid decomposition. The catalyst has the advantages of being porous, multiple in active sites and the like, has multiple pore structures in the synthesis process, can effectively load Pd nano-particles in the catalyst, and maintains good overall morphology before and after loading. The catalyst can be used as a catalyst for decomposing formic acid to generate hydrogen, and has excellent catalytic performance at 60 DEG C.

The invention discloses preparation of a ligand-modified palladium-carbon catalyst and application of the ligand-modified palladium-carbon catalyst in selective hydrogenation reaction of mifepristone, a carrier of the catalyst is amino ligand-modified activated carbon, an active component is noble metal Pd, the noble metal Pd is uniformly loaded on the carrier, the loading amount of Pd in the catalyst is 1-10%, and the loading amount of Pd in the catalyst is 1-10%. And the content of the positive valence Pd in the catalyst accounts for 40-60% of the total amount of the noble metal Pd element. A series of palladium carbon catalysts modified by different ligands are generated through a dipping reduction method, hydroxyl on the surface of the modified carrier can provide appropriate sites for amino ligand grafting, then amino protonation adsorbs metal ions through electrostatic interaction, and the metal dispersity is improved; and the Pd nanoparticles loaded on the carrier are smaller in size and more uniform in distribution. When the catalyst disclosed by the invention is applied to the semi-hydrogenation reaction of the mifepristone to prepare the amcopristone, the selectivity of the amcopristone is up to 96%, and the conversion rate is greater than 99%.

The invention discloses preparation and application of a Pd nano particle modified hydrogen production photocatalytic material, and relates to the field of catalysts.A UiO-66-NH2 material is prepared through a hydrothermal method, then a semiconductor material dicerium trisulfide is loaded on the surface of UiO-66-NH2 through a precipitation method, oxygen vacancy defects are introduced on the surface of a Ce2S3 / UiO-66-NH2 heterostructure through a chemical reduction method, and the Pd nano particle modified hydrogen production photocatalytic material is obtained. The Pd nanoparticles are used as a photo-induced electron capture center, and are induced and anchored on the surface of the material in combination with a photodeposition method, so that the high-dispersity Pd nanoparticle modified hydrogen production photocatalytic material is finally prepared. Introduction of oxygen vacancies in the composite material and the surface plasma resonance effect of Pd nanoparticles can effectively improve the light absorption capacity, a built-in electric field formed in a heterostructure of the composite material can drive photo-generated charges to move directionally and reduce the recombination rate of the photo-generated charges, and the photocatalytic hydrogen production efficiency of the composite material can be enhanced through the synergistic effect of the two.

The present application relates to the field of gas detection, in particular to a titanium carbide composite material, a preparation method thereof and a hydrogen detection application. The titanium carbide composite material comprises Ti3C2T x substrate and Pd nanoparticles loaded on the Ti3C2T x substrate. The Ti3C2T x substrate is a multilayer structure, and at least part of the Pd nanoparticles are loaded between the layers of the Ti3C2T x substrate multilayer structure. The hydrogen sensor using the titanium carbide composite material of the present application can detect hydrogen with high sensitivity and high selectivity in a room temperature environment.

The invention discloses an amino-functionalized rodlike silicon dioxide loaded monometal Pd nano-catalyst and application thereof, after rodlike silicon dioxide is subjected to surface modification by 3-aminopropyltrimethoxysilane, a Pd precursor solution and amino-functionalized rodlike silicon dioxide are mixed, and loaded Pd nano-particles are subjected to reduction treatment by sodium borohydride. Compared with a traditional spherical silicon dioxide carrier, the unique morphology of the rod-like silicon dioxide carrier adopted by the catalyst provides a high specific surface area and a short mass transfer channel, the anchoring capacity of Pd nanoparticles is improved through amino functionalization, sintering is inhibited, and efficient and uniform loading and small size control of single metal Pd are achieved. The catalyst is used for room-temperature formic acid decomposition hydrogen production reaction, and shows 100% formic acid conversion rate, 100% hydrogen selectivity, good cycling stability and high initial TOF (Time of Flight) value.

The invention relates to a palladium molecular sieve catalyst and a preparation method and application thereof, the preparation method comprises the following steps: (1) mixing palladium salt with an organic solvent, and adding a high-silicon molecular sieve carrier to obtain a catalyst precursor; and (2) carrying out non-equilibrium thermal shock treatment on the catalyst precursor, and cooling to obtain the palladium molecular sieve catalyst. A non-equilibrium thermal shock method is adopted, second-level transient heating is used for promoting in-situ decomposition and anchoring of a Pd precursor on the surface of the molecular sieve, Pd nano-particles which are uniform in particle size and uniform in dispersion are obtained, and the problem that precious metal is sintered and gathered in the steady-state roasting process is effectively solved; the catalyst shows excellent low-temperature activity and long-term stability in methane catalytic combustion reaction, effectively solves the problem of catalyst deactivation caused by high temperature and high water vapor in industrial waste gas treatment, and has important application potential in the field of environmental protection such as gas engine waste gas and coal mine gas treatment.

The invention discloses application of a composite hollow nanotube array which is coated with an MOF hydrophobic layer and has a core-sheath structure in gas-sensitive moisture resistance. The preparation method of the composite hollow nanotube array comprises the following steps: (1) synthesizing a ZnO nanowire on a substrate in situ as an array template; growing on the surface of the ZnO nanowire through a hydrothermal method to obtain an etching layer containing Sn, and sintering the etching layer containing Sn to obtain a SnO2 hollow nanotube array; and (2) loading Pd nano-particles and coating an MOF hydrophobic layer on the surfaces of nano-tubes of the SnO2 hollow nano-tube array in sequence to obtain the composite hollow nano-tube array. The composite hollow nanotube array has excellent sensitivity and selectivity, the lower limit of detection can reach the ppm level, the response speed is high, and the anti-humidity effect is good.

The present invention discloses an optical hydrogen sensing material, a preparation method thereof, and a method for optically detecting hydrogen concentration. The optical hydrogen sensing material comprises a non-continuous thin film structure composed of densely arranged Pd nanoparticles. The preparation method is based on cluster beam deposition technology, in which Pd nanoparticles are deposited at a low deposition rate on the surface of a highly transparent quartz plate to form a disordered nanoparticle film with a certain visible light absorbance. Due to the interaction between the Pd nanoparticles, the particles are mutually coupled through the excited surface plasmon resonance, thereby presenting a significant plasmon resonance peak in the optical absorption spectrum. When the Pd nanoparticles reversibly adsorb hydrogen, the optical absorption spectrum will undergo significant quantitative changes depending on the external hydrogen concentration, thereby realizing the hydrogen sensing function. The key point in the preparation of the hydrogen gas-sensitive film is to deposit the Pd nanoparticles at an appropriate deposition rate to form a specific nanoparticle assembly structure and obtain a more stable sensor baseline.

This application relates to the field of catalyst technology, disclosing an electron-rich Pd nanocatalyst, its preparation method, and its application. The electron-rich Pd nanocatalyst comprises a sheet-like Mg(OH)₂ support and Pd nanoparticles uniformly loaded on the sheet-like Mg(OH)₂ support; wherein the thickness of the Mg(OH)₂ sheet is less than 2 nm; and the average particle size of the Pd nanoparticles is less than 4 nm. The preparation method includes dispersing the Mg(OH)₂ support in water, sequentially adding a palladium source and urea, refluxing at 55-65°C to obtain a precursor solution; adding a reducing agent to the precursor solution to carry out the reaction, collecting the solid deposit, washing, and drying to obtain the final product. This application, by regulating the electronic structure of the Pd nanoparticles, significantly increases the electron density on their surface, increasing the repulsion of reaction products, weakening the adsorption of reaction products on the catalyst surface, avoiding poisoning of the catalyst active sites, and improving the reactivity and selectivity of the Pd nanocatalyst for the hydrogenation of nitrile compounds at low temperatures.

The application provides a catalyst and a preparation method, application and a preparation method of tetrahydrofurfuryl alcohol, the catalyst uses mesoporous silica as a carrier, the surface of the carrier is modified with polyethylene glycol and an alkyl chain to form an amphiphilic surface, and Pd nanoparticles are loaded in the mesopores. The mesoporous silica supported palladium catalyst has an amphiphilic interface formed by polyethylene glycol and an alkyl chain modified on the surface through a covalent bond, the hydrophilic polyethylene glycol chain enriches furfuryl alcohol molecules through hydrogen bonds, and the hydrophobic alkyl chain captures hydrogen microbubbles, which can effectively reduce the gas-liquid interfacial tension, is helpful to the breaking of large bubbles and the stable existence of nanobubbles, and makes the preparation of tetrahydrofurfuryl alcohol realize efficient reaction under significantly reduced pressure.

The invention discloses a light-driven heterojunction nano-robot as well as a preparation method and application thereof. The light-driven heterojunction nano-robot takes palladium (Pd) nanoparticles as a carrier and is loaded with copper sulfide (CuS); according to the light-driven heterojunction nano-robot, Pd nano-particles serve as a chassis, CuS is loaded on the tail portions of the Pd nano-particles, heterojunction nano-enzyme is formed, H2O2 is efficiently catalyzed to generate. OH, cancer cell immunogenicity death is mediated, meanwhile, the light-driven heterojunction nano-robot is provided with a power system, and the light-driven heterojunction nano-robot can move under light driving; in addition, the head of the Pd nanoparticle is loaded with a neutrophil exosome modified by triphenylphosphine and loaded with lactate oxidase, and the light-driven heterojunction nano-robot with the navigation effect is obtained.

The invention discloses a CeO2 loaded noble metal nanoparticle and a low-temperature dispersion method. The method comprises the following steps: (1) mixing cerium oxide and metal platinum salt or metal palladium salt, and grinding to obtain solid powder; (2) roasting the solid powder obtained in the step (1) in an oxygen atmosphere; (3) roasting the solid powder obtained in the step (2) in a hydrogen atmosphere to obtain Pt or Pd nanoparticles loaded on the CeO2 carrier; and (4) carrying out low-temperature roasting treatment on the Pt or Pd nanoparticles loaded on the CeO2 carrier obtained in the step (3) in an NO atmosphere to obtain further dispersed Pt / CeO2 or Pd / CeO2. According to the method, the supported metal nanoparticles can be further dispersed at the low temperature of 200-400 DEG C, meanwhile, elements such as Cl do not need to be additionally introduced, the treatment method is simple, and industrial application prospects are achieved.