6results about How to "Reduced bandgap width" patented technology

The invention discloses a preparation method of a composite material for improving the utilization rate of solar blue-green photocatalytic degradation of water pollutants, which comprises the following steps: firstly, preparing a Cu-ZnO nano composite material by doping zinc oxide with copper ions, and reducing the forbidden band width, so that the Cu-ZnO nano composite material can utilize sunlight with longer wavelength, and the absorption peak of the Cu-ZnO nano composite material generates red shift; secondly, decolorizing the wood by adopting an alkaline sodium sulfate method, removing lignin in the wood to leave a cavity, and growing the Cu-ZnO nano composite material in the treated wood and on the surface of the treated wood by adopting a hydrothermal method to form a composite material with a catalyst growing in a similar resonant cavity, as shown in Figure 1; the utilization rate of a semiconductor catalyst to blue-green light is improved, a cavity structure formed by the treated wood can have a certain local effect on long-wavelength light, the purpose of fully utilizing long-wave sunlight for multiple times is achieved, and the blue-green photocatalytic efficiency is improved.

The invention belongs to the technical field of photocatalysis, and particularly relates to a BiOCl / UiO-66 (Zr / Ce) heterojunction photocatalyst as well as a preparation method and application thereof. According to the invention, UiO-66 (Zr) is taken as a matrix, a new metal node Ce is introduced, and electron transfer among different metals is utilized, so that the band gap of a single BiOCl material is effectively reduced, and the charge separation efficiency is improved. BiOCl is constructed on UiO-66 (Zr / Ce) to form a heterojunction, and the interface property of the BiOCl / UiO-66 (Zr / Ce) heterojunction is regulated and controlled through the doped metal Ce, so that the interface electric field of the BiOCl / UiO-66 (Zr / Ce) heterojunction is enhanced, effective separation of photon-generated carriers is promoted under the action of the electric field, enough active sites and electron transport performance are provided, and the photocatalytic efficiency of the BiOCl / UiO-66 (Zr / Ce) heterojunction is further improved.

The invention discloses a Co3O4-Cu2-xS composite photo-thermal catalyst as well as a preparation method and application thereof. The composite photo-thermal catalyst is prepared by taking a surfactant as a bridge and compounding Co3O4 and Cu2-xS. The composite photo-thermal catalyst has a reduced band gap width, can effectively promote migration and separation of photon-generated carriers, enhances the absorption efficiency of visible light-near infrared light, and shows excellent photo-thermal conversion performance. The composite photo-thermal catalyst can be used for constructing a Co3O4-Cu2-xS + PMS + NIR catalytic system, and peroxymonosulfate is activated under the irradiation of near-infrared light so as to degrade antibiotics in water. Experiments prove that the Co3O4-Cu2-xS + PMS + NIR system disclosed by the invention can achieve the degradation rate of 99% on levofloxacin within 20 minutes, and the generation efficiency of active species is remarkably improved through the synergistic effect of a photothermal effect and interface activation. The catalyst has broad-spectrum degradation activity on various antibiotics, keeps efficient and stable catalytic performance in a wide pH range, and shows excellent ion interference resistance and adaptability to various water bodies.

The invention discloses a method for synthesizing a chromium ion-doped tungsten oxide complete photolysis water catalyst flat reactor, comprising the following steps: step 1: fully dissolving sodium tungstate and chromium acetate in water and then mixing with glacial acetic acid to obtain a reaction solution, wherein the volume ratio of water to glacial acetic acid is 1:1, wherein the concentrations of sodium tungstate, chromium acetate, citric acid or trisodium citrate are 0.01-1 mol L −1 , 1×10 −3 ~0.4 mol L −1 , 0~2 mol L −1 , and the molar ratio of sodium tungstate, chromium acetate, citric acid or trisodium citrate in the solution is maintained at 1:0.1~0.4:0~2, and then transferred to a stainless steel autoclave reactor with a polytetrafluoroethylene liner. The synthesis method of the present invention significantly improves the activity of the complete photocatalyst for water splitting (solar energy → hydrogen (STH) conversion efficiency value 4.3%~6.1%), service life, and reduces its cost price.

This invention discloses an additive manufacturing-based inertial amplification nonlinear low-frequency vibration isolation metamaterial structure, vibration isolation device, and its performance control method. The vibration isolation metamaterial structure includes a rhombic frame structure, an inertial amplification unit, and a square spring structure. The square spring structure is arranged within the rhombic frame structure, with its two ends connected to a pair of opposite corners of the rhombic frame structure. The elastic extension direction of the square spring structure is parallel to the diagonal of this pair of opposite corners of the rhombic frame structure. The inertial amplification unit has a centrally symmetrical structure, including a rigid rod, two counterweights, and two diagonal rods. The center of symmetry of the inertial amplification unit, the center of the rhombic frame structure, and the center of the square spring structure all coincide in projection. Therefore, the vibration isolation metamaterial structure of this invention significantly widens the bandgap range and enhances low-frequency vibration isolation performance, exhibiting excellent performance in suppressing longitudinal waves in the 0-1000Hz low-frequency range, increasing vibration damping, and energy absorption.

The present invention belongs to the technical field of wastewater treatment, and specifically relates to a method for treating ammonia nitrogen wastewater containing heavy metals. The treatment method comprises preparing and modifying C3N4 nanosheets, adding a forming agent and the prepared modified C4N3 nanosheets to a polar organic solvent for blending, and preparing a photocatalytic cation exchange membrane through forming, film scraping, and solidification; and placing the photocatalytic cation exchange membrane in an electrolytic cell, with an anode chamber and a cathode chamber on both sides, and placing ammonia nitrogen wastewater containing heavy metals and sulfuric acid respectively, using a light source to irradiate the photocatalytic cation exchange membrane to catalyze the degradation of ammonia nitrogen, and at the same time, making the heavy metal ions complexed with ammonia nitrogen become free heavy metal ions; after the heavy metal ions pass through the photocatalytic cation exchange membrane, they are reduced at the cathode through electrolysis to obtain metal elements. The present invention can remove ammonia nitrogen and heavy metals at the same time, and has the advantages of low energy consumption, low use cost, and thorough treatment without secondary pollution.