62results about How to "Improve hydrogen production activity" patented technology

The invention discloses Ni-doped Cd0.1Zn0.9 S microsphere photocatalyst and the preparation method thereof, the particle shape of the produced photocatalyst is a microsphere formed by nanometer crystals, and the doping amount of Ni is 0.1 percent to 0.5 percent of the weight of the catalyst. The invention has the preparation method that zinc sulfate, cadmium sulfate, nickel nitrate, and thioacetamide are taken as raw materials to form mixed solution which is sealed in a hydrothermal caldron and then laid in a baking oven to be insulated, naturally cooled to the room temperature, a resultant is obtained through cleaning, drying, and grinding. The Ni-doped Cd0.1Zn0.9S microsphere photocatalyst is prepared by the invention, and the anti-surface oxidation capability in air and the photo-corrosion resistant capability in the photocatalytic reaction are evenly enhanced greatly. Because the particle of the photocatalyst is microsphere-shaped, the photocatalytic activity for photocatalytic water splitting into hydrogen of visible light of the catalyst is greatly enhanced, and the highest hydrogen production rate reaches 191.01 micromole / (g*h). The quantum efficiency reaches 6.77 percent at the 420 nm position. After Pt of 0.6 wt percent is loaded, the highest hydrogen production rate reaches 585.45 micromole / (g*h), which is three times than the hydrogen production rate when the Pt is not loaded. The quantum efficiency reaches 15.9 percent at the 420 nm position, the activity is high, and the stability is good.

The invention discloses a preparation method of a precious-metal-free high-activity photocatalytic-water-splitting hydrogen-producing catalyst. In the invention, photocatalytically hydrogen-producing activities of a precious-metal-free NiOx-CdS photocatalyst, a precious-metal-free Ni-CdS photocatalyst and a precious-metal-free flower-shaped Ni / Ni(OH)2-CdS photocatalyst are all better than that of Pt-CdS, wherein the NiOx-CdS photocatalyst, the Ni-CdS photocatalyst and the Ni / Ni(OH)2-CdS photocatalyst are prepared respectively through an in-situ photodeposition method, a hydrothermal reduction method and a hydrothermal method. NiOx and Ni can effectively transfer and separate photoproduced electronics and holes so that the photocatalytically hydrogen-producing activity of the catalyst is enhanced. In addition, because of an unique flower-shaped structure of the flower-shaped Ni / Ni(OH)2, CdS can be inserted into a laminated structure of the Ni / Ni(OH)2 well and be contacted tightly with the Ni / Ni(OH)2, thereby forming a composite catalyst having an excellent photocatalytically hydrogen-producing activity under a photochemical effect.

The invention belongs to the field of preparation and application of photocatalysts, and relates to a visible-light-driven NiSe2-based heterojunction photocatalyst for producing hydrogen through efficient photocatalytic water splitting. The NiSe2 / CdS heterojunction photocatalyst is synthesized through a second-step solvothermal method by firstly preparing CdS nano rods by taking cadmium nitrate and thiourea as a cadmium source and a sulfur source respectively and adopting a solvothermal method, then performing a hydrothermal reaction by taking nickel nitrate hexahydrate, hexamethylenetetramine, trisodium citrate and the synthesized CdS nano rods as substrates and taking deionized water as a solvent, then cooling, then adding an NaHSe solution, and then continuing to raise the temperature for reacting. The heterojunction photocatalyst involved in the invention has high hydrogen production rate in visible light; a preparation method is environmentally friendly; the operation is simple; the activity is stable; the utilization rate of the photocatalyst to sunlight, especially the visible light, is greatly improved; higher economic benefit can be obtained.

The invention discloses a fluorine-substituted Zn / Co porphyrin-based conjugated organic polymer as well as a preparation method thereof and application thereof. Required raw materials are wide in source, the synthesis process is easy to control, a Sonogashira coupling reaction is adopted to expand the light absorption range of a porphyrin complex to a near-infrared light region, and the transfer of photo-induced electrons between Zn and Co center metals can be accelerated, and the recombination of the electrons and holes is reduced, so that photons in an ultraviolet-visible-near-infrared lightregion are effectively utilized to realize efficient photocatalytic hydrogen production, and a good application prospect is shown in the aspect of photocatalytic hydrogen production with wide spectral response.

The invention discloses metal oxide nanoparticles as well as a preparation method and application thereof. Specifically, the invention discloses the metal oxide nanoparticles which ares prepared by the following steps: 1) dissolving an alkali inorganic salt into a reductive solvent, performing uniform mixing, adding an inorganic salt of a metal, and performing uniform stirring so as to obtain a homogeneous solution; 2) under a condition of an inert gas, performing a vacuum heating reaction, wherein the heating temperature is 150-600 DEG C; and 3) performing centrifugal separation on a solid, and performing washing and drying, so as to obtain metal oxide nanospheres. The method disclosed by the invention is simple, the prepared metal oxide nanospheres have a uniform particle size and a goodhydrogen generation ability, and the metal oxide is a metal oxide with the lowest valence.

The invention relates to the technical field of photocatalytic hydrogen generation, specifically to a 0D / 2D composite photocatalysis material and a preparation method and application thereof. The preparation method comprises the following steps: weighing a certain amount of ammonium molybdate and thioacetamide and dissolving the raw materials in deionized water to obtain a mixed solution, pouringthe mixed solution into a certain amount of a newly prepared Cu-In-Zn-S quantum dot solution, followed by uniform ultrasonic mixing; pouring the above solution into a high pressure reactor, placing the high pressure reactor into a drying oven of 180 DEG C, reacting for 16 h, and cooling to room temperature; and finally carrying out deionized water / ethanol ethanol precipitation / centrifugation circulatory washing on a compound for three times, drying the washed sample in a drying oven of 60 DEG C to obtain Cu-In-Zn-S / MoS2 nanocrystal. The experiment of visible light photocatalytic water splitting for hydrogen production proves that the prepared composite photocatalyst has a good photocatalytic activity.

The invention discloses a supported photocatalyst NiSe / Mn0.5Cd0.5S and a preparation method thereof. The supported photocatalyst is prepared by firstly synthesizing a Mn0.5Cd0.5S solid solution by using a gentle one-step hydrothermal method, and by secondly, enabling the solid solution to react with nickel sulfate hexahydrate and sodium selenite. NiSe and Mn0.5Cd0.5S are tightly combined to form heterojunctions in the composite catalyst, migration of photon-generated carriers can be facilitated, combination of photon-generated electron holes is inhibited, and the photocatalysis hydrogen production activity of the Mn0.5Cd0.5S solid solution can be remarkably improved. The novel NiSe / Mn0.5Cd0.5S photocatalyst disclosed by the invention is simple to prepare, can be massively prepared, is highin photocatalysis activity and good in stability, and has wide application prospects in clean energy development.

A photocatalyst Pt-carried CdS / Ti-MCM-41 for generating H2 by optical catalytic reaction is prepared through providing CTAB as template agent, hydrothermal reaction to synthesize CTAB / Ti-MCM-41, ion exchange to obtain Cd / Ti-MCM-41, sulfurizing in HS gas to obtain CdS / Ti-MCM-41 and carrying Pt by optical reduction method. It has high H2 output rate.

The invention relates to a preparation method of monoclinic system tungsten trioxide. The preparation method of the monoclinic system tungsten trioxide comprises the following steps: (1) while stirring, adding nitric acid into sodium tungstate solution, stirring, then carrying out centrifugal separation, and collecting to obtain yellow precipitate; (2) transferring the yellow precipitate into a reactor, and adding deionized water, organic acid solution and polyethylene glycol solution; (3) then adding the nitric acid, and stirring for 0.5-2 hours; and (4) transferring the obtained slurry into an autoclave, sealing, then heating to the temperature of 160-250 DEG C, and continuously reacting for 8-20 hours, so that monoclinic system tungsten trioxide powder is obtained. The preparation method provided by the invention has the advantages that uniformly dispersed micro-nano tungsten trioxide crystal particles are obtained, and the obtained tungsten trioxide crystal particles have excellent photocatalytic performance.

The invention discloses an ultraviolet-visible-near infrared responded PbS / TiO2 nanotube aggregation microsphere heterostructure as well as a preparation method and an application thereof. The ultraviolet-visible-near infrared responded PbS / TiO2 nanotube aggregation microsphere heterostructure provided by the invention has the characteristics that the heterostructure can be porous microsphere particles which are obtained by enabling PbS nanocrystals to be distributed on the surfaces of TiO2 nanotubes in TiO2 nanotube aggregation microspheres, wherein the particle diameter range of each PbS nanocrystal is 25nm to 36nm, the particle size of the TiO2 nanotube is not more than 10nm, and the diameter distribution of the aggregation microspheres is within the range of 0.2 micron to 7 micron. Thebonding force between the PbS and the TiO2 nanotube in the heterostructure is strong, and the heterostructure has good ultraviolet-visible-near infrared responded photocatalytic hydrogen production activity, and higher hydrogen production is almost realized in the full spectrum range.

The invention discloses a loaded photocatalyst NiSe / Mn 0.5 Cd 0.5 S and preparation method thereof, it is to adopt mild one-step hydrothermal method to synthesize Mn earlier 0.5 Cd 0.5 S solid solution, and then react it with nickel sulfate hexahydrate and sodium selenite. NiSe and Mn in the composite catalyst 0.5 Cd 0.5 S is closely combined to form a heterojunction, which is beneficial to the migration of photogenerated carriers and inhibits the recombination of photogenerated electrons and holes, making Mn 0.5 Cd 0.5 The photocatalytic hydrogen production activity of S solid solution was significantly improved. The novel NiSe / Mn that the present invention uses 0.5 Cd 0.5 S photocatalyst has the advantages of simple preparation, mass preparation, high photocatalytic activity and good stability, which makes it have broad application prospects in the development of clean energy.