摘要:
The present invention relates to a photocatalyst for the generation of diatomic hydrogen from a hydrogen containing precursor under the influence of actinic radiation comprising a semiconductor support with one or more noble and/or transition metal(s) deposited on said semiconductor support, wherein said metal is covered at least in part with a layer of the semiconductor support. Further disclosed is a method for preparing such catalyst and a method for generating diatomic hydrogen by photolysis.
摘要:
Disclosed is a photocatalyst, and methods for its use, that includes a photoactive material comprising a photonic band gap and an electronic band gap, wherein the photonic band gap at least partially overlaps with the electronic band gap, and an electrically conductive material deposited on the photoactive material.
摘要:
Present disclosure provides a process for the synthesis of visible light responsive doped titania photocatalysts. The process involves step a) milling a mixture containing titania and a precursor compound, the compound selected from the group consisting of chloroauric acid and a mixture containing chloroauric acid and silver nitrate, in the presence of water and oxide milling media, at a temperature in the range of 20 to 50° C. for a period of 60-120 minutes, to form a slurry, wherein the amount of water is in the range of 15 to 25% by weight of the total mixture; and b) filtering the slurry to separate the oxide milling media and obtain a filtrate containing doped titania nanoparticles.
摘要:
A monolithic catalyst system for the cleavage of water into hydrogen and oxygen comprises a first photoactive material capable by itself or together with an auxiliary material and/or an auxiliary catalyst when irradiated with light having a wavelength≧420 nm of generating oxygen and protons from water, and a second photoactive material capable by itself or together with an auxiliary material and/or an auxiliary catalyst when irradiated with light having a wavelength≧420 nm of reducing protons in water to hydrogen. The first and second photoactive materials are in electrical contact via an electron-conducting material.
摘要:
The invention belongs to the technical field of preparing oxalate in coal to ethylene glycol, aiming at providing a preparation process for nanocatalysts with (111) crystal facet exposed and a process for vapour-phase CO oxidative coupling to oxalate. The nanocatalysts with (111) crystal facet exposed comprise carrier, active component and promoter on the carrier, wherein, in term of the weight of the carrier, the active component accounts for 0.05-2% of the weight of the carrier, the weight percentage of metal elements in the promoter is 20% or less. The nanocatalysts with (111) crystal facet exposed are prepared by the nanometals in situ supporting process. The preparation process is simple in procedure, has low energy consumption and can precisely control the size and exposed crystal facet of the active component nanoparticles. The obtained nanocatalysts with (111) crystal facet exposed are highly active for vapour-phase CO oxidative coupling to oxalate at a lower loading of noble metal.
摘要:
This invention discloses a method for fabricating a gold/titanium dioxide core-shell structured photocatalyst and the application thereof to photocatalytic decomposition of organic compounds under ultraviolet irradiation. The method comprises steps: fabricating a solution of gold ions; fabricating gold/titanium dioxide core-shell structured nanoparticles; and crystallizing the gold/titanium dioxide core-shell structured nanoparticles, wherein gold and titanium dioxide are mixed by a weight ratio of 0.005 to 0.03. The gold/titanium dioxide core-shell structured photocatalyst can effectively decompose organic compounds and dyes under ultraviolet irradiation.
摘要:
The invention relates to a method for preparing a substrate surface structured with thermally stable metal alloy nanoparticles, which method comprises—providing a micellar solution of amphiphilic molecules such as organic diblock or multiblock copolymers in a suitable solvent; —loading the micelles of said micellar solution with metal ions of a first metal salt; —loading the micelles of said micellar solution with metal ions of at least one second metal salt; —depositing the metal ion-loaded micellar solution onto a substrate surface to form a (polymer) film comprising an ordered array of (polymer) domains; co-reducing the metal ions contained in the deposited domains of the (polymer) film by means of a plasma treatment to form an ordered array of nanoparticles consisting of an alloy of the metals used for loading the micelles on the substrate surface. The invention also provides a nanostructured substrate surface obtainable by said method as well as the use of said nanostructured substrate surface as a catalyst.
摘要:
A method of fabricating composite filaments is provided. An initial composite filament including a core and a cladding (such as a Pt-group metal) is cut into smaller pieces (or is first mechanically reduced and then cut into smaller pieces). The smaller pieces of the filaments are inserted into a metal matrix, and the entire structure is then further reduced mechanically in a series of reduction steps. The process can be repeated until the desired cross sectional dimension of the filaments is achieved. The matrix can then be chemically removed to isolate the final composite filaments with the cladding thickness down to the nanometer range. The process allows the organization and integration of filaments of different sizes, compositions, and functionalities into arrays suitable for various applications. Materials and components made from such composite filaments and arrays of composite filaments are also disclosed,
摘要:
A method of making a supported catalytic species comprising an alloy of at least two metals, comprises the steps of: (i) combining a particulate support material, a solution of a first metal compound, a solution of a second metal compound, and a solution of an alkaline precipitating agent to form a slurry mixture; (ii) agitating the resultant mixture; and (iii) contacting the solids with a reducing agent, wherein the first metal in the first metal compound and the second metal in the second metal compound is each independently selected from the group consisting of gold, palladium, platinum, rhodium, iridium, silver, osmium and ruthenium; and wherein the first metal is not the same as the second metal.
摘要:
A catalyst for use in at the anode of direct methanol fuel cells is made from nanoparticles having a core-shell structure. The core is an alloy of platinum and gold. The core is surrounded by a first shell of ruthenium and a second shell containing a ternary alloy of platinum, gold, and ruthenium. The catalyst can be made by a reverse-micelle method or by a single-phase scalable method. The catalyst is highly stable under conditions of use and resists dissolution of ruthenium or platinum.