Method for preparing modified TiO2 coatings by sol-gel method

Abstract

The invention discloses a method for preparing modified TiO2 coatings by a sol-gel method, which comprises the following steps that: (1) chemical pure tetrabutyl orthotitanate Ti(OC4O9)4 is used as raw materials, ethanol is used as solvents, acetylacetone (CH3CO)2CH2 is adopted as complexing agents for preparing light yellow TiO2 sol, and the TiO2 sol is subjected to still sanding and aging for use; (2) five layers of coatings are coated on the aged TiO2 sol by a dip coating method; (3) five-layer coating samples are placed into a vacuum plating instrument (ionization N2 atmosphere), the temperature is raised to the required temperature by a certain procedure, the heat insulation is carried out for 2 hours, then, the materials are cooled along with a furnace, the doping process of carbon and nitrogen is completed, and the carbon and nitrogen doping TiO2 coatings (TNC) are prepared; and (4) the prepared carbon and nitrogen doping TiO2 coatings are placed into a muffle furnace to be annealed for 2 hours at 450 DEG C, and the annealed carbon and nitrogen doping TiO2 coatings (TTNC) are prepared. The modified TiO2 coatings are prepared through novel ion doping by the sol-gel method, the light-catalysed activity of the TiO2 is improved, and simultaneously, the coatings have better thermal stability.

Description

technical field [0001] The present invention relates to a kind of TiO 2 The preparation method of the coating particularly relates to a method for preparing a high-temperature coating for solar energy on the surface of a metal substrate and a glass substrate by a sol-gel method. Background technique [0002] TiO 2 As a wide bandgap semiconductor, it has the advantages of stable properties, safety and non-toxicity, and high photocatalytic activity. But since TiO 2 The forbidden band width is 3.2eV, and it can only show catalytic activity under the excitation of ultraviolet light. However, in sunlight, the energy of ultraviolet light (below 400nm) accounts for only 4%, while the energy of visible light (400-750nm) accounts for 43%. How? Modified TiO 2 It has been a research hotspot to make it active under the excitation of visible light or even indoor light source. TiO 2 Common methods of modification include transition metal ion doping, noble metal deposition, fuel sensi...

AI Technical Summary

Problems solved by technology

But since TiO 2 The forbidden band width is 3.2eV, and it can only show catalytic activity under the excitation of ultraviolet light. However, in sunlight, the energy of ultraviolet light (below 400nm) accounts for only 4%, while the energy of visible light (400-750nm) accounts for 43%. How? Modified TiO 2 It has been a research hotspot to make it active under the excitation of visible light or even indoor light source. TiO 2 Common methods of modification include transition metal ion doping, noble metal deposition, fuel sensitization, compound semiconductors, etc., which can make the compound bandgap of the compound smaller than that of TiO 2 The bandgap width, so that TiO 2 The absorption edge moves towards visible light, but the above method still needs to be perfected and improved in terms of thermal stability and light utilization rate. The present invention overcomes the above TiO 2 Modified technical defects, a new type of modified TiO 2 coating, so that the composite bandgap of the composite is smaller than that of TiO 2 The bandgap width, so that TiO 2 The absorption edge of TiO moves to the visible light, which improves the TiO 2 photocatalytic activity, while the coating has better thermal stability