炭黑吸附水热法制备纳米TiO_2粉体及其光催化降解甲基橙

Preparation and Photocatalytic Degradation for Methyl Orange of Nano-powder TiO_2 by Hydrothermal Method Supported on Activated Carbon

利用炭黑吸附钛酸异丙酯水热法制得锐钛矿型TiO2纳米粉体。采用热重/差热分析(TG-DTA)、X-射线衍射(XRD)、扫描电镜(SEM)、比表面积吸附(BET)和紫外-可见光谱(UV-VIS)等分析方法对不同煅烧机制下所得粉体的物相、颗粒度、分散性和光吸收性能进行表征。同时利用纳米TiO2粉体对甲基橙进行了光催化降解,研究了其光催化性能。结果表明,炭黑的吸附阻止了纳米TiO2超细颗粒的团聚和烧结,制得的颗粒分散均匀、具有单一锐钛矿晶型结构的TiO2纳米粉体。经500℃煅烧获得的TiO2粉体粒径约为15 nm,比表面积为76.31 g/m2。在紫外灯照射下,由于炭黑的吸附和纳米TiO2的光催化形成协同效应,甲基橙的光催化降解率在6 min达到99%。

Anatase nano-titania was prepared by hydrothermal method with tetraisopropyl titanate supported activated carbon. The obtained powder were characterized by thermo gravimetrie-differential thermal analysis （ TG-DTA ）, X-ray diffraction （ XRD ）, Scanning electron microscope （ SEM ）, BET surface area and UV-Vis absorption spectrometer（UV-Vis）. Activated carbon acted as a barrier which prevents powder agglomeration, controlled the growth of TiO2 particles size and increases the surface area of photocatalyst during the drying and calcinations process. The TiO2 powder with carbon calcined at 500 ℃ was found to be mainly pure anatase phase. The crystal have good dispersion, average particle size is around 15 nm, surface area is 76.31 g/m2. The photocatalytic degradation activity was studied with the TiO2 powder for the methyl orange under UV light. The results showed that the absorption of carbon black and photo catalytic properties of TiO2 have a synergistic effect, the photocatalytic degradation rates of methyl orange could reach 99% within 6 min.