(南京師范大學(xué) 化學(xué)與材料科學(xué)學(xué)院,南京 210097)
摘 要: 以鈦酸四丁酯、硝酸鉍及尿素為前驅(qū)體,利用溶劑熱法制備氮摻雜BixTiOy-TiO2復(fù)合催化劑,利用X射線衍射(XRD)、紫外-可見漫反射 (UV-Vis)、場發(fā)射掃描電鏡(FE-SEM)、X射線光電子能譜(XPS)和低溫氮氣吸附(BET)等手段對樣品進行表征,以亞甲藍為模型化合物,考察各催化劑在模擬太陽光下的光催化活性。結(jié)果表明:由于一定量的氮摻雜可增強催化劑中Bi12TiO20的含量,氮摻雜的復(fù)合催化劑在440~520nm處出現(xiàn)了較大的吸收;氮摻雜使催化劑從圓球形變?yōu)榛ò晷危龃罅舜呋瘎┑谋缺砻娣e和羥基自由基的含量。氮摻雜量為0.15%(質(zhì)量分數(shù))的BNT2催化劑在250 W金鹵燈模擬太陽光下照射3 h后,對20 mg/L的亞甲基藍溶液的去除率為93.86%,比相同條件下BT和NT催化劑的去除效率分別提高了32%和37.31%。
關(guān)鍵字: 復(fù)合半導(dǎo)體;溶劑熱法;氮摻雜;光催化活性;功能材料
(School of Chemistry and Environmental Science, Nanjing Normal University, Nanjing 210097, China)
Abstract:N-doped BixTiOy-TiO2 composite catalysts were prepared by solvothermal synthesis using tetrabutyl titanate, bismuth nitrate and urea as precursors. The particles were characterized by X-ray diffractometry (XRD), ultraviolet-visible diffuse reflectance spectroscopy (UV-Vis), field emission scanning electron microscopy (FE-SEM), X-ray photoelectron spectroscopy (XPS) and Brunauer-Emmett-Teller (BET). The photocatalytic activity of the catalysts was investigated via photodegradation of methylene blue under simulated sunlight irradiation. The results show that the content of Bi12TiO20 increases due to nitrogen doping. A significant absorption at 440-520 nm for N-doped BixTiOy-TiO2 composite catalysts appears, the catalysts turn from spherical into a petal shape which can be ascribed to nitrogen doping resulting in the increase of surface area as well as content of hydroxyl radicals. The best removal rate of methylene blue solution (20 mg/L) reaches 93.86% under Haloid lamp of 250 W after 3 h with the nitrogen dosage of 0.15% (mass fraction), increase by 32% and 37.31% separately compared with Bi-doped TiO2 and N-doped TiO2 under the same conditions.
Key words: compound semiconductor; solvothermal method; N-doping; photocatalytic activity


