The Preparation And Research On Visible Light Response Of Titanium Dioxide Photocatalyst

Photocatalyst has a broad application prospect in the field of environmental pollution control and purification because it can show great catalytic performance and can effectively degrade environmental pollutants under the condition of light. Nanometer TiO2 is a kind of new photocatalytic materials,which as a cheap, efficient, clean and green light catalyst,can degrade various toxic gases and oxidation various organic compounds, into harmless compounds under the irradiation of ultraviolet light.However, the light catalyst has many problems such as preparation methods are complicated、not productive and unable to practical application. The comercial TiO2 photocatalytic materials has effect only under ultraviolet light and the ultraviolet light only account for 5% of the sunlight total energy.Therefore,it is a important problem to solve that TiO2’s lighttenergy utilization rate is low.For one hand,we should contral TiO2’s band gap to expand the spectrum, to make it absorb part of the visible light and improve the utilization efficiency of light energy. Studies have shown that,through mental doping, absorption of nanometer TiO2 photocatalyst will move to the visible light spectrum and greatly improve the catalytic efficiency and performance;Anhoter hand,it is important to find no pollution, low energy consumption, high efficiency of artificial light source, is conducive to its practical application.LED is a good choice because it has broad application in future.This paper used sol-gel method, prepared metal nickel, copper, zinc doped nanometer TiO2 precursor which have different morphology at room temperature. Characterizing the samples with SEM、BET and other means, do the photocatalytic degradation of methylene blue experiments under the LED, ultraviolet light, xenon light source. Tests results showed that the preparation of nanometer particles’size is around 50 nm and specific surface area are more than 250m2/g.The sample which with 350℃ calcination has the best photocatalytic properties,in the 465 nm led light its photocatalytic effect is far better than P25.Using different light sources we found nickel metal doped TiO2 particles has better catalytic effect than copper doping in visible light, confirming that nickel doping nano TiO2 can significantly alter the forbidden band gap and make it has efficient visible light response.This experiment increase the efficiency of nanometer TiO2, providing theory basis for its large-scale application in the future.