CN101623658A - Preparation method of compound nanotube photocatalytic film of titanium dioxide and silicon dioxide - Google Patents

Abstract

The invention relates to a preparation method of a compound nanotube photocatalytic film of titanium dioxide and silicon dioxide, which belongs to the field of nanofilms. At present, the problem of easy compound of photo-excited holes and electron pairs of a titanium dioxide photocatalytic film causes that the titanium dioxide photocatalytic film has lower efficiency when being applied to sewage treatment. The preparation method comprises the following steps: adopting anodic aluminum oxide (AAO) as a template and dipping the AAO into a mixed solution of (NH4)2TiF6 and (NH4)2SiF6 at 30-40 DEG C for co-deposition in-situ growth by utilizing a liquid-phase deposition method so as to prepare the compound nanotube photocatalytic film of titanium dioxide and silicon dioxide with a good appearance; after cleaning and drying the prepared film, preparing the compound nanotube photocatalytic film of titanium dioxide and silicon dioxide with high photocatalytic performance by carrying out heat treatment and preserving heat for 2-4 hours at 400-600 DEG C. The preparation method completes the nanofilm and compound treatment at one time, and the film has strong repeatability, is convenient for mass production and can get a treatment efficiency of 70-95 percent after being applied to a photocatalytic reaction of a methyl blue solution of 100mg/L (0.1wt%).

Description

The preparation method of compound nanotube photocatalytic film of titanium dioxide and silicon dioxide

Technical field:

A kind of preparation method of compound nanotube photocatalytic film of titanium dioxide and silicon dioxide in particular, utilizes anodised aluminium AAO template liquid phase codeposition compound nanotube photocatalytic film of titanium dioxide and silicon dioxide, belongs to the nano thin-film field.

Background technology:

The energy and environmental pollution are the matters of utmost importance that the 21 century mankind face.Nanometer technology and the combination of conductor photocatalysis technology are applied to environmental protection and improvement, have brought new opportunity for environmental pollution and improvement aspect.Nano-TiO ₂With its excellent photocatalysis performance, caused the extensive concern of domestic and international material supply section educational circles, become one of focus of developmental research.

Though nano-TiO ₂Photochemical catalyst is nontoxic with it, oxidability is strong, good stability and the most commonly used but it in use remains following problems at present: (1) nano-TiO ₂Particle is tiny, in wastewater treatment process, easily causes with current and loses waste, reclaims very difficult.(2) efficiency of light absorption is lower, and the titanium oxide nanotubes that has high-specific surface area by preparation is one of effective means that improves its optical absorption characteristics.(3) photohole-duplet is very easily compound and lost catalytic action, thereby from economic angle, how to improve nano-TiO ₂Photocatalysis efficiency, avoiding compound is a urgent problem.

The compound main direction of studying that solves photohole-duplet at present concentrates on carries out Combined Processing to nano titanium oxide, the for example preparation of titanium dioxide and silica composite, its preparation method mainly concentrates on and uses sol-gel process, and for example patent CN11894594 provides the method for preparing silica and mesoporous titanium dioxide complex with sol-gel process.Patent CN1244516A provides the method for preparing the titanium dioxide and silicon dioxide composite powder with Ludox and titanium colloidal sol.But, Zhi Bei composite titanium dioxide and gold/SO 2 mesoporous composite body technology more complicated in this way, generally need twice processing, promptly finish mesoporous preparation earlier and carry out Combined Processing then, though Zhi Bei nano composite powder can once be finished in this way, but finally be difficult to solve its loading problem, in sewage disposal process, be difficult to reclaim, easily cause secondary pollution.

Summary of the invention

Problem to be solved by this invention provides a kind of method for preparing compound nanotube photocatalytic film of titanium dioxide and silicon dioxide.Not only solve the loading problem of nano titanium oxide, and prepare titanium dioxide and silica composite nano tube by the liquid phase codeposition, can improve photocatalysis efficiency to a certain extent, promptly reduce the compound problem of photoproduction-duplet, technology is simple, and a step finishes.

The preparation method of a kind of compound nanotube photocatalytic film of titanium dioxide and silicon dioxide provided by the present invention is characterized in that: may further comprise the steps:

(1) the metal aluminium flake is carried out anodized, the electrolyte solution that adopts is H ₃PO ₄, concentration is 0.5-1.5M, oxidation voltage 80-100V, oxidization time 8-12h;

(2) use by the alumina nano tube array that obtains after the anodized as template, with standby after washed with de-ionized water and the oven dry;

(3) with (NH of 0.05-0.5M ₄) ₂TiF ₆(NH with 0.05-0.5M ₄) ₂SiF ₆Mixed liquor is mixed into a liquid deposition solution by Si atom and Ti atomic molar ratio for 0.05-0.5;

(4) anodised aluminium nano-tube array template is placed above-mentioned liquid deposition solution leave standstill deposition 15-30min, temperature is 30-40 ℃, takes out and uses washed with de-ionized water, and oven dry obtains film;

(5) film after will drying is heat-treated insulation 2-4h at 400-600 ℃, cools to room temperature then with the furnace, and preparation is finished.

The invention has the beneficial effects as follows:

Owing to adopted (NH ₄) ₂TiF ₆(NH ₄) ₂SiF ₆The liquid phase codeposition technique, the compound nanotube photocatalytic film of titanium dioxide and silicon dioxide of the present invention's preparation has good nanotube pattern, technical process of the present invention is different from conventional silicon dioxide and titanium dioxide complex technique and carries out behind the preparation titania nanotube compound earlier, because of adopting the liquid phase co-electrodeposition method to omit follow-up Combined Processing, simplified preparation technology, process repeatability is strong, is convenient to large-scale production; In addition, utilize compound nanotube photocatalytic film of titanium dioxide and silicon dioxide that the present invention prepares under different deposition temperatures, deposit solution proportioning and sedimentation time that the photocatalytic degradation experimental result of 100mg/L (0.1wt%) methyl blue solution is shown: treatment effeciency reaches 70%-95% after the 2-5h.Excellent photocatalysis performance and simple preparation technology make compound nanotube photocatalytic film of titanium dioxide and silicon dioxide have wide practical use.

Description of drawings:

Fig. 1: TiO ₂And SiO ₂Before compound nanotube photocatalytic film codeposition preparation figure (a) deposition in (b) deposition after (c) deposition

Fig. 2: the ESEM front view (SEM) of compound nanotube photocatalytic film of titanium dioxide and silicon dioxide

The scanning electron microscope (SEM) photograph of compound nanotube photocatalytic film of titanium dioxide and silicon dioxide of the present invention, accelerating potential are 30kV, and 30000 times of multiplication factors are taken along the vertical thin-film direction. Among the figure as seen, titanium dioxide and silicon dioxide composite nano tube marshalling, the aperture is about 30-100nm.

The specific embodiment:

Embodiment one:

The metal aluminium flake is carried out anodized, and adopting concentration is the H of 0.5M ₃PO ₄Be electrolyte solution, oxidation voltage 100V, oxidization time 10h.The aluminium substrate of grown after the anodic oxidation anodic oxidation aluminium formwork (AAO) is taken out with standby after the washed with de-ionized water.With 0.5mol/L (NH ₄) ₂TiF ₆And 0.5mol/L (NH ₄) ₂SiF ₆Mixed liquor is in atom content Si: the Ti=5% ratio is mixed into a liquid deposition solution, and fully stirs, and places 30 ℃ of water-baths standby.The AAO template is immersed (NH ₄) ₂TiF ₆(NH ₄) ₂SiF ₆Take out behind the deposition 15min in the mixed liquor, with washed with de-ionized water and oven dry.The 400 ℃ of following insulation 3h that heat up subsequently cool to room temperature with the furnace.

Embodiment two:

The metal aluminium flake is carried out anodized, and adopting concentration is the H of 0.5M ₃PO ₄Be electrolyte solution, oxidation voltage 80V, oxidization time 12h.The aluminium substrate of grown after the anodic oxidation anodic oxidation aluminium formwork (AAO) is taken out with standby after the washed with de-ionized water.With 0.1mol/L (NH ₄) ₂TiF ₆And 0.1mol/L (NH ₄) ₂SiF ₆Mixed liquor is in atom content Si: the Ti=10% ratio is mixed into a liquid deposition solution, and fully stirs, and places 35 ℃ of water-baths standby.The AAO template is immersed (NH ₄) ₂TiF ₆(NH ₄) ₂SiF ₆Take out after stirring deposition 20min in the mixed liquor, with washed with de-ionized water and oven dry.The 500 ℃ of following insulation 2h that heat up subsequently cool to room temperature with the furnace.

Embodiment three:

The metal aluminium flake is carried out anodized, and adopting concentration is the H of 1M ₃PO ₄Be electrolyte solution, oxidation voltage 100V, oxidization time 10h.The aluminium substrate of grown after the anodic oxidation anodic oxidation aluminium formwork (AAO) is taken out with standby after the washed with de-ionized water.With 0.05mol/L (NH ₄) ₂TiF ₆And 0.05mol/L (NH ₄) ₂SiF ₆Mixed liquor is in atom content Si: the Ti=20% ratio is mixed into a liquid deposition solution, and fully stirs, and places 40 ℃ of water-baths standby.The AAO template is immersed (NH ₄) ₂TiF ₆(NH ₄) ₂SiF ₆Take out after stirring deposition 30min in the mixed liquor, with washed with de-ionized water and oven dry.The 500 ℃ of following insulation 3h that heat up subsequently cool to room temperature with the furnace.

Embodiment four:

The metal aluminium flake is carried out anodized, and adopting concentration is the H of 1M ₃PO ₄Be electrolyte solution, oxidation voltage 80V, oxidization time 12h.The aluminium substrate of grown after the anodic oxidation anodic oxidation aluminium formwork (AAO) is taken out with standby after the washed with de-ionized water.With 0.1mol/L (NH ₄) ₂TiF ₆And 0.1mol/L (NH ₄) ₂SiF ₆Mixed liquor is in atom content Si: the Ti=30% ratio is mixed into a liquid deposition solution, and fully stirs, and places 35 ℃ of water-baths standby.The AAO template is immersed (NH ₄) ₂TiF ₆(NH ₄) ₂SiF ₆Take out after stirring deposition 20min in the mixed liquor, with washed with de-ionized water and oven dry.The 600 ℃ of following insulation 4h that heat up subsequently cool to room temperature with the furnace.

Embodiment five:

The metal aluminium flake is carried out anodized, and adopting concentration is the H of 1.5M ₃PO ₄Be electrolyte solution, oxidation voltage 100V, oxidization time 8h.The aluminium substrate of grown after the anodic oxidation anodic oxidation aluminium formwork (AAO) is taken out with standby after the washed with de-ionized water.With 0.1mol/L (NH ₄) ₂TiF ₆And 0.1mol/L (NH ₄) ₂SiF ₆Mixed liquor is in atom content Si: the Ti=40% ratio is mixed into a liquid deposition solution, and fully stirs, and places 35 ℃ of water-baths standby.The AAO template is immersed (NH ₄) ₂TiF ₆(NH ₄) ₂SiF ₆Take out after stirring deposition 30min in the mixed liquor, with washed with de-ionized water and oven dry.The 500 ℃ of following insulation 3h that heat up subsequently cool to room temperature with the furnace.

Embodiment six:

The metal aluminium flake is carried out anodized, and adopting concentration is the H of 1.5M ₃PO ₄Be electrolyte solution, oxidation voltage 80V, oxidization time 12h.The aluminium substrate of grown after the anodic oxidation anodic oxidation aluminium formwork (AAO) is taken out with standby after the washed with de-ionized water.With 0.05mol/L (NH ₄) ₂TiF ₆And 0.05mol/L (NH ₄) ₂SiF ₆Mixed liquor is in atom content Si: the Ti=40% ratio is mixed into a liquid deposition solution, and fully stirs, and places 40 ℃ of water-baths standby.The AAO template is immersed (NH ₄) ₂TiF ₆(NH ₄) ₂SiF ₆Take out after stirring deposition 30min in the mixed liquor, with washed with de-ionized water and oven dry.The 500 ℃ of following insulation 3h that heat up subsequently cool to room temperature with the furnace.

Embodiment seven:

The metal aluminium flake is carried out anodized, and adopting concentration is the H of 1M ₃PO ₄Be electrolyte solution, oxidation voltage 100V, oxidization time 12h.The aluminium substrate of grown after the anodic oxidation anodic oxidation aluminium formwork (AAO) is taken out with standby after the washed with de-ionized water.With 0.1mol/L (NH ₄) ₂TiF ₆And 0.1mol/L (NH ₄) ₂SiF ₆Mixed liquor is mixed into a liquid deposition solution in silicon atom content 50% ratio, and fully stirs, and places 35 ℃ of water-baths standby.The AAO template is immersed (NH ₄) ₂TiF ₆(NH ₄) ₂SiF ₆Take out after stirring deposition 30min in the mixed liquor, with washed with de-ionized water and oven dry.The 550 ℃ of following insulation 3h that heat up subsequently cool to room temperature with the furnace.

The present invention is provided with 3 subordinate lists altogether, now is respectively described below:

Energy spectrogram (EDS) the elementary analysis table of table 1 compound nanotube photocatalytic film of titanium dioxide and silicon dioxide

Element	Percentage by weight	Atomic percent
			??O	??43.29	??59.96
??Al	??23.66	??19.85
			??Si	??9.72	??7.83
??P	??3.54	??2.58
			??Ti	??20.69	??9.77
Total amount	??100	??100

The table 2 compound nanotube photocatalytic film of titanium dioxide and silicon dioxide methyl blue solution numerical tabular that is used to degrade

Table 3 pure titinium dioxide nanotube and compound nanotube photocatalytic film of titanium dioxide and silicon dioxide be used to the to degrade numerical value contrast table of methyl blue solution

Claims (1)

1, a kind of preparation method of compound nanotube photocatalytic film of titanium dioxide and silicon dioxide is characterized in that: may further comprise the steps:

(1) the metal aluminium flake is carried out anodized, the electrolyte solution that adopts is H ₃PO ₄, concentration is 0.5-1.5M, oxidation voltage 80-100V, oxidization time 8-12h;

(2) use by the alumina nano tube array that obtains after the anodized as template, with standby after washed with de-ionized water and the oven dry;

(3) with (NH of 0.05-0.5M ₄) ₂TiF ₆(NH with 0.05-0.5M ₄) ₂SiF ₆Mixed liquor is mixed into a liquid deposition solution by Si atom and Ti atomic molar ratio for 0.05-0.5;

(4) anodised aluminium nano-tube array template is placed above-mentioned liquid deposition solution leave standstill deposition 15-30min, temperature is 30-40 ℃, takes out and uses washed with de-ionized water, and oven dry obtains film;

(5) film after will drying is heat-treated insulation 2-4h at 400-600 ℃, cools to room temperature then with the furnace, and preparation is finished.