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CN-118237058-B - Preparation method and application of gold/bismuth oxide@manganic oxide Z-type heterojunction photocatalyst

CN118237058BCN 118237058 BCN118237058 BCN 118237058BCN-118237058-B

Abstract

The invention relates to a preparation method of a gold/bismuth oxide carbonate@manganous oxide Z-type heterojunction photocatalyst. The preparation method comprises preparing Bi 2 O 2 CO 3 fiber flower ball with Bi (NO 3 ) 3 •5H 2 O and C 6 H 8 O 7 •H 2 O as reactants in neutral solution; the nano Au particles are loaded by an electrostatic self-assembly method and are dispersed on the surface of the Bi 2 O 2 CO 3 fiber flower ball to prepare an Au/Bi 2 O 2 CO 3 sample; dispersing Au/Bi 2 O 2 CO 3 into dimethylformamide solution, dropping Mn (CH 3 COO) 2 •4H 2 O solution) under ultrasonic condition to obtain Au/Bi 2 O 2 CO 3 core-shell structure sample coated by Mn 3 O 4 nano particles, the photocatalyst has high-efficiency photogenerated carrier separation efficiency and strong NO oxidation capability under visible light, has remarkable degradation activity on pollutants, and has wide application prospect in the field of photocatalysis.

Inventors

  • XU XIAOMING
  • HUANG JIAYING
  • ZHU XIANHUI
  • YUAN RUIXIA
  • JING GUOLIN
  • ZHENG LIHUI
  • CAO WENZHONG
  • YANG SHAOGUI
  • SUN CHENG

Assignees

  • 东北石油大学

Dates

Publication Date
20260508
Application Date
20240329

Claims (10)

  1. 1. The preparation method of the gold/bismuth oxide@manganous oxide Z-type heterojunction photocatalyst is characterized by comprising the following steps of: Dissolving Bi (NO 3 ) 3 •5H 2 O in dilute nitric acid solution, then adding C 6 H 8 O 7 •H 2 O, magnetically stirring until the solution is clear, adjusting the pH to 7, heating by an autoclave, washing by water and ethanol, and drying in vacuum to obtain a Bi 2 O 2 CO 3 sample; Step 2, mixing and transferring the oleylamine containing HAuCl 4 •4H 2 O with a toluene solution to a high-pressure reaction kettle for heating, cooling the obtained product to room temperature, adding ethanol, centrifuging to obtain nano Au particles, dispersing the nano Au particles into cyclohexane by ultrasonic and stirring to form a red dispersion, and mixing the red dispersion with 3-mercaptopropionic acid into a flask; Stirring the obtained mixed solution in the step 2 at room temperature, centrifuging, washing the precipitate with acetone, dispersing the precipitate into deionized water through ultrasonic and stirring to obtain a nano Au particle suspension solution, mixing Bi 2 O 2 CO 3 and polyvinylpyrrolidone-K30 with the nano Au particle suspension solution, and carrying out ultrasonic, stirring, washing and vacuum drying to obtain an Au/Bi 2 O 2 CO 3 sample; dispersing Au/Bi 2 O 2 CO 3 material into dimethylformamide solution, gradually dripping Mn (CH 3 COO) 2 •4H 2 O solution under ultrasonic condition, and obtaining a solid sample after ultrasonic and centrifugal treatment; And 5, dispersing the sample obtained in the step 4 into deionized water, sealing in an autoclave, heating to improve the crystallinity of Mn 3 O 4 , washing and drying in vacuum to obtain a final product.
  2. 2. The method for preparing the gold/bismuth oxide carbonate@manganomanganic oxide Z-type heterojunction photocatalyst according to claim 1, wherein the heating temperature of the autoclave in the step 1 is 150-200 ℃, and the mass ratio of Bi (NO 3 ) 3 .5H2O to C 6 H 8 O 7 •H 2 O is 0.73:0.21.
  3. 3. The method for preparing the gold/bismuth oxide carbonate@manganous oxide Z-type heterojunction photocatalyst according to claim 1, wherein the heating temperature in the step 2 is 50-150 ℃ and the heating time is 10-15h.
  4. 4. The method for preparing the gold/bismuth oxide carbonate@manganous oxide Z-type heterojunction photocatalyst according to claim 1, wherein the volume ratio of oleylamine to toluene in the step 2 is 3:37, and the volume ratio of cyclohexane to 3-mercaptopropionic acid is 2:1.
  5. 5. The preparation method of the gold/bismuth oxide@manganous oxide Z-type heterojunction photocatalyst according to claim 1, wherein the mass ratio of Bi 2 O 2 CO 3 to polyvinylpyrrolidone-K30 (PVP-K30) in the step 3 is 3:2, the mass ratio of Au to Bi 2 O 2 CO 3 is 1% -10%, and the obtained mixed solution is stirred for 10-15h at room temperature.
  6. 6. The method for preparing the gold/bismuth oxide carbonate@manganous oxide Z-type heterojunction photocatalyst according to claim 1, wherein the concentration of Mn (CH 3 COO) 2 •4H 2 O solution is 0.01-0.05mol/L; and the volume ratio of dimethylformamide to Mn (CH 3 COO) 2 •4H 2 O solution is 9:1) in the step 4.
  7. 7. The method for preparing the gold/bismuth oxide carbonate@manganous oxide Z-type heterojunction photocatalyst according to claim 1, wherein the mass ratio of Mn 3 O 4 to 12% in the solid sample in the step 4.
  8. 8. The preparation method of the gold/bismuth oxide carbonate@manganous oxide Z-type heterojunction photocatalyst according to claim 1, wherein the autoclave heating temperature in the step 5 is 100-150 ℃, the heating treatment is 4-6h, the vacuum drying temperature is 50-80 ℃ and the vacuum drying is 8h.
  9. 9. The use of the gold/bismuth oxide carbonate @ trimanganese tetraoxide Z-heterojunction photocatalyst prepared by the preparation method of claim 1 in NO oxidation.
  10. 10. The gold/bismuth oxide/manganous oxide Z-heterojunction photocatalyst prepared by the preparation method of claim 1, and the application thereof in the degradation of clothianidin.

Description

Preparation method and application of gold/bismuth oxide@manganic oxide Z-type heterojunction photocatalyst Technical Field The invention relates to the technical field of nano photocatalytic materials, in particular to a preparation method and application of a gold/bismuth oxide@manganous oxide Z-type heterojunction photocatalyst. Background The nitrogen oxides are not only the main reasons of acid rain formation and ozone layer destruction, but also the human health is endangered, in addition, the nitrogen oxides and various hydrocarbon compounds are subjected to chemical reaction, and the toxicity of the obtained products is several times stronger than that of the products, so that the atmospheric environment is extremely severely polluted. Therefore, the control of nitrogen oxides is one of the most urgent and necessary tasks in the field of atmospheric pollution control in China. The photocatalysis technology is focused on and widely applied to the fields of pollutant degradation and nitrogen oxide oxidation due to the characteristics of energy conservation, environmental protection, no toxicity, mild reaction conditions and the like. Among the various semiconductor photocatalysts, bismuth-based materials have the advantages of low cost, high activity and the like, wherein Bi 2O2CO3 is taken as a novel double-base catalyst, has double-layer alternating phases, and has high photogenerated carrier separation efficiency, and is widely studied. However, pure Bi 2O2CO3 has a wider band gap, resulting in lower light energy utilization and catalytic activity. Therefore, the invention adopts the supported noble metal and the cocatalyst to construct a Z-type heterojunction system, in the system, the separation efficiency of the photo-generated carriers is higher, and meanwhile, the visible light absorption range is expanded by changing the band gap structure, so that the catalytic activity of the photocatalyst is greatly improved, and the invention can be applied to NO oxidation and the degradation of the pollutant clothianidin. Disclosure of Invention The invention provides a preparation method of a gold/bismuth oxide@manganic oxide Z-type heterojunction photocatalyst, which aims to solve the problem that the existing semiconductor double-base photocatalyst is low in light energy utilization rate and catalytic activity due to the fact that the band gap of pure Bi 2O2CO3 is wide. The invention aims to provide a preparation method of a gold/bismuth oxide@manganous oxide Z-type heterojunction photocatalyst, which can improve the separation efficiency of photogenerated carriers, and simultaneously expand the visible light absorption range by changing a band gap structure, so that the catalytic activity of the photocatalyst is greatly improved. The invention also provides application of the gold/bismuth oxide@manganous oxide Z-type heterojunction photocatalyst. The first object of the invention is to provide a preparation method of a gold/bismuth oxide/manganous oxide Z-type heterojunction photocatalyst, which comprises the following steps: Dissolving Bi (NO 3)3·5H2 O in dilute nitric acid solution, then adding C 6H8O7·H2 O, magnetically stirring until the solution is clear, adjusting the pH to 7, heating by an autoclave, washing by water and ethanol, and drying in vacuum to obtain a Bi 2O2CO3 sample; Step 2, mixing and transferring the oleylamine containing HAuCl 4·4H2 O with a toluene solution to a high-pressure reaction kettle for heating, cooling the obtained product to room temperature, adding ethanol, centrifuging to obtain nano Au particles, dispersing the nano Au particles into cyclohexane by ultrasonic and stirring to form a red dispersion, and mixing the red dispersion with 3-mercaptopropionic acid into a flask; Stirring the obtained mixed solution in the step 2 at room temperature, centrifuging, washing the precipitate with acetone, dispersing the precipitate into deionized water through ultrasonic and stirring to obtain a nano Au particle suspension solution, mixing Bi 2O2CO3 and polyvinylpyrrolidone-K30 (PVP-K30) with the nano Au particle suspension solution, and carrying out ultrasonic, stirring, washing and vacuum drying to obtain an Au/Bi 2O2CO3 sample; Dispersing Au/Bi 2O2CO3 material into Dimethylformamide (DMF) solution, gradually dripping Mn (CH 3COO)2·4H2 O solution under ultrasonic condition, and obtaining a solid sample after ultrasonic and centrifugal treatment; And 5, dispersing the sample obtained in the step 4 into deionized water, sealing in an autoclave, heating to improve the crystallinity of Mn 3O4, washing and drying in vacuum to obtain a final product. Preferably, the heating temperature of the autoclave in the step 1 is 150-200 ℃, and the mass ratio of Bi (NO 3)3.5H2O to C 6H8O7·H2 O is 0.73:0.21. Preferably, the heating temperature in the step 2 is 50-150 ℃ and the heating time is 10-15 hours. Preferably, the volume ratio of oleylamine to toluene in step 2 is 3:37 and the volume r