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CN-122010169-A - Preparation method of nanorod hydrosol and application of nanorod hydrosol in concrete

CN122010169ACN 122010169 ACN122010169 ACN 122010169ACN-122010169-A

Abstract

The invention discloses a preparation method of a nano rod hydrosol and application of the nano rod hydrosol in concrete, wherein the preparation method comprises the steps of enabling a titanium compound to react in the presence of H 2 O 2 , a catalyst Fe 3 O 4 and water, the reaction temperature is 50-100 ℃, the nano rod hydrosol is selected from TiO 2 nano rod hydrosol or TiO 2 -SiO 2 composite nano rod hydrosol, the content of SiO 2 in the TiO 2 -SiO 2 composite nano rod hydrosol is 0.5-2wt%, the titanium compound is Ti (OH) 4 or Ti (OH) 4 @SiO 2 , and the Ti (OH) 4 @SiO 2 is formed by compounding SiO 2 on the surface of Ti (OH) 4 in situ. According to the invention, siO 2 is introduced into a TiO 2 system, the high specific surface area and excellent adsorptivity of SiO 2 are conducive to enriching reactants on the surface of TiO 2 , so that the photocatalytic efficiency is improved, and meanwhile, the excellent chemical inertness and film forming property are used for remarkably improving the mechanical stability and interfacial adhesion of the coating.

Inventors

  • HAN XIANYING
  • SUN QIKAI
  • ZHANG YINGXUAN
  • LI JIANGANG
  • LIU YUE

Assignees

  • 北京石油化工学院

Dates

Publication Date
20260512
Application Date
20251215

Claims (10)

  1. 1. A method for preparing a nanorod hydrosol is characterized by comprising the steps of reacting a titanium compound in the presence of H 2 O 2 、Fe 3 O 4 and water; Wherein the nano rod hydrosol is selected from TiO 2 nano rod hydrosol or TiO 2 -SiO 2 composite nano rod hydrosol, and the content of SiO 2 in the TiO 2 -SiO 2 composite nano rod hydrosol is 0.5-2wt%; The titanium compound is Ti (OH) 4 or Ti (OH) 4 @SiO 2 , wherein Ti (OH) 4 @SiO 2 is formed by compounding SiO 2 on the surface of Ti (OH) 4 in situ; The molar ratio of Ti to H 2 O 2 in the titanium compound is 1 (4-15); The molar ratio of Ti to Fe 3 O 4 in the titanium compound is (70-130): 1; The temperature of the reaction is 50 ℃ to reflux temperature; The reaction time is 1-8 hours.
  2. 2. The method according to claim 1, wherein the molar ratio of Ti to H 2 O 2 in the titanium compound is 1 (4-15); And/or the molar ratio of Ti to Fe 3 O 4 in the titanium compound is (70-130) 1; And/or the concentration of Fe 3 O 4 in the reaction system is 0.2-0.5 mmol/L; and/or the reaction temperature is 50-100 ℃; The reaction time is 1-8 hours; And/or the pressure of the reaction is normal pressure; And/or the length of the nano rod hydrosol is 50-100 nm, and/or the diameter of the nano rod hydrosol is 5-10 nm.
  3. 3. The method according to claim 1, characterized in that the preparation method comprises the steps of: (1) Mixing a titanium compound Ti (OH) 4 or Ti (OH) 4 @SiO 2 with an aqueous solution of H 2 O 2 to prepare a precursor solution; (2) And (3) mixing the precursor solution obtained in the step (1) with Fe 3 O 4 , and heating for reaction to obtain the nanorod hydrosol.
  4. 4. A method according to claim 3, wherein in step (1), the precursor is a titanium peroxo complex precursor; And/or the concentration of the titanium peroxide complex in the precursor solution is 0.01-0.05 mol/L; And/or, in the step (1), the preparation method of the Ti (OH) 4 @SiO 2 serving as the titanium compound comprises the steps of mixing Ti (OH) 4 dispersion liquid with a silicon source solution, carrying out hydrolysis reaction under alkaline conditions, and standing and aging the obtained mixed liquid to form an SiO 2 layer on the surface of Ti (OH) 4 in situ to obtain Ti (OH) 4 @SiO 2 .
  5. 5. The method according to claim 4, wherein in the preparation method of Ti (OH) 4 @SiO 2 , the Ti (OH) 4 dispersion is a water and ethanol dispersion of Ti (OH) 4 ; And/or the concentration of Ti (OH) 4 in the Ti (OH) 4 dispersion is 0.005-2 g/mL; And/or, in the preparation method of Ti (OH) 4 @SiO 2 , the silicon source is selected from tetraethoxysilane; And/or, in the preparation method of Ti (OH) 4 @SiO 2 , the silicon source solution is ethanol solution of a silicon source, and the volume concentration of the silicon source solution is 1-10vol%; And/or, in the preparation method of Ti (OH) 4 @SiO 2 , in the Ti (OH) 4 dispersion, the ratio of the mass of Ti (OH) 4 corresponding to the generation of TiO 2 to the mass of SiO 2 corresponding to the added silicon source is 1 (0.001-0.05); And/or, in the preparation method of Ti (OH) 4 @SiO 2 , the temperature of the hydrolysis reaction is 15-35 ℃, and the time of the hydrolysis reaction is 2-10h; And/or, in the preparation method of Ti (OH) 4 @SiO 2 , the temperature of standing aging is 15-35 ℃ and/or the time of standing aging is 2-48h.
  6. 6. The method of claim 1, wherein the method for preparing the TiO 2 nanorod hydrosol comprises the steps of: (S1) mixing Ti (OH) 4 with an aqueous solution of H 2 O 2 to prepare a titanium peroxide complex precursor solution; (S2) mixing the titanium peroxide complex precursor solution in the step (1) with Fe 3 O 4 , and heating for reaction to prepare the TiO 2 nanorod hydrosol; And/or in the step (S2), the concentration of the titanium peroxide complex in the titanium peroxide complex precursor solution is 0.01-0.05 mol/L; And/or in the step (S2), the concentration of Fe 3 O 4 in the titanium peroxide complex precursor solution is 0.2-0.5 mmol/L.
  7. 7. The method of claim 1, wherein a method for preparing a TiO 2 -SiO 2 composite sol, the method comprising: (K1) Mixing Ti (OH) 4 dispersion liquid with silicon source solution, carrying out hydrolysis reaction under alkaline condition, and standing and aging the obtained mixed liquid to generate SiO 2 layer on the surface of Ti (OH) 4 in situ to obtain Ti (OH) 4 @SiO 2 ; (K2) Mixing Ti (OH) 4 @SiO 2 with H 2 O 2 water solution and Fe 3 O 4 for reaction to prepare TiO 2 -SiO 2 composite sol; And/or, in step (K2), the reaction is carried out in water, wherein the concentration of titanium ions in Ti (OH) 4 @SiO 2 in water is 0.01-0.06mol/L; And/or, in the step (K2), the content of SiO 2 in the TiO 2 -SiO 2 composite sol is 0.5-2wt%.
  8. 8. The nanorod hydrosol prepared by the method of any one of claims 1-7, wherein the nanorod hydrosol comprises a TiO 2 nanorod hydrosol and/or a TiO 2 -SiO 2 composite sol.
  9. 9. The use of the nanorod hydrosol according to claim 8 in concrete, And/or, using TiO 2 nano-rod hydrosol and/or TiO 2 -SiO 2 composite sol in concrete.
  10. 10. A photocatalytic coating for a concrete surface, wherein the TiO 2 nanorod hydrosol and/or the TiO 2 -SiO 2 composite sol according to claim 8 is coated on the surface of the concrete.

Description

Preparation method of nanorod hydrosol and application of nanorod hydrosol in concrete Technical Field The invention belongs to the technical field of functional nano materials and concrete, and particularly relates to a preparation method of nanorod hydrosol and application of the nanorod hydrosol in the concrete. Background Concrete is used as a core material for modern building and bridge engineering, the surface performance of the concrete directly influences structural attractiveness, durability and maintenance cost, and particularly in high-rise buildings and bridges, the long-term stability and safety of the concrete are important. Along with the acceleration of the urban process, the development of a concrete surface coating with a self-cleaning function becomes a research hot spot. The coating can effectively remove surface pollutants, degrade harmful substances in the atmosphere, prolong the service life of a building, reduce the maintenance cost and realize the harmonious symbiosis of the building and the environment. Titanium dioxide (TiO 2) is a typical semiconductor photocatalytic material that can generate hydroxyl radicals (.oh) and superoxide radicals (.o 2-) under light, thereby effecting photocatalytic oxidative degradation of organic contaminants. However, the conventional sol-gel process for preparing high crystallinity TiO 2 generally requires heat treatment at 400-600 ℃, which is liable to cause particle agglomeration, grain coarsening and reduction in sol stability, thereby reducing photocatalytic performance and increasing energy consumption. In addition, the existing TiO 2 coating is easy to have the problems of insufficient adhesive force, cracking or peeling and the like in the service process, so that the long-term application of the coating in the field of concrete is limited. Disclosure of Invention In order to solve the technical problems, the invention provides a preparation method of nanorod hydrosol, which comprises the steps of reacting a titanium compound in the presence of H 2O2、Fe3O4 and water; Wherein the nano rod hydrosol is selected from TiO 2 nano rod hydrosol or TiO 2-SiO2 composite nano rod hydrosol, and the content of SiO 2 in the TiO 2-SiO2 composite nano rod hydrosol is 0.5-2wt%; The titanium compound is Ti (OH) 4 or Ti (OH) 4@SiO2, wherein Ti (OH) 4@SiO2 is formed by compounding SiO 2 on the surface of Ti (OH) 4 in situ; The molar ratio of Ti to H 2O2 in the titanium compound is 1 (4-15); the molar ratio of Ti to Fe 3O4 in the titanium compound is (70-130): 1; The temperature of the reaction is 50 ℃ to reflux temperature; The reaction time is 1-8 hours. According to an embodiment of the invention, the molar ratio of Ti to H 2O2 in the titanium compound is 1 (4-15), e.g. 1 (8-12), e.g. 1 (9-11), e.g. 1 (9.5-10.5), e.g. 1:9.5, 1:9.8, 1:10, 1:10.2 or 1:10.5. According to an embodiment of the invention, the molar ratio of Ti to Fe 3O4 in the titanium compound is (70-130): 1, for example 80-120:1, examples of which are selected from 80:1, 90:1, 100:1, 110:1 or 120:1. According to an embodiment of the invention, the concentration of Fe 3O4 in the reaction system is 0.2-0.5 mmol/L, for example 0.2 mmol/L, 0.25 mmol/L, 0.3 mmol/L, 0.35 mmol/L, 0.4 mmol/L, 0.45 mmol/L or 0.5 mmol/L. According to an embodiment of the invention, fe 3O4 acts as a catalyst for the reaction. According to an embodiment of the invention, the temperature of the reaction is 50-100 ℃, for example 50℃、55℃、60℃、65℃、70℃、75℃、80℃、81℃、82℃、83℃、84℃、85℃、86℃、87℃、88℃、89℃、90℃、91℃、92℃、93℃、94℃、95℃、96℃、97℃、98℃、99℃、100℃. According to an embodiment of the invention, the reaction time is 1 to 8 hours, for example 1h, 2h, 4h, 6h or 8h. According to an embodiment of the invention, the pressure of the reaction is atmospheric pressure. According to the embodiment of the invention, the length of the nanorod hydrosol is 50-100 nm, and/or the diameter of the nanorod hydrosol is 5-10 nm. According to an embodiment of the invention, the preparation method comprises the steps of: (1) Mixing a titanium compound Ti (OH) 4 or Ti (OH) 4@SiO2 with an aqueous solution of H 2O2 to prepare a precursor solution; (2) And (3) mixing the precursor solution obtained in the step (1) with Fe 3O4, and heating for reaction to obtain the nanorod hydrosol. According to an embodiment of the invention, in step (1), the aqueous H 2O2 solution has a concentration of 15-30wt%, preferably 20-30wt%. According to an embodiment of the invention, in step (1), the molar ratio of Ti to H 2O2 in Ti (OH) 4 is 1 (4-15), e.g. 1 (8-12), e.g. 1 (9-11), e.g. 1 (9.5-10.5), e.g. 1:9.5, 1:9.8, 1:10, 1:10.2 or 1:10.5. According to an embodiment of the present invention, in step (1), the precursor is a titanium peroxo complex precursor. Preferably, the concentration of the titanium peroxide complex in the precursor solution is 0.01-0.05 mol/L, preferably 0.02-0.05 mol/L. According to an embodiment of the present invention, in the step (2), the heating reaction is p