负载型TiO_2/SBA-15的制备及其光催化还原CO_2性能  

Synthesis of Supported TiO_2/SBA-15 Catalysts and Their Performance on Photocatalytic Reduction of CO_2

作　　者：王会香[1,2] 姜东[1] 吴东[1] 李德宝[1] 孙予罕[1] 

机构地区：[1]中国科学院山西煤炭化学研究所煤转化国家重点实验室,太原030001 [2]中国科学院大学,北京100049

出　　处：《化学学报》2012年第23期2412-2418,共7页Acta Chimica Sinica

基　　金：国家自然科学基金(No.21003150);山西省自然科学基金(No.2011011006-2);煤转化国家重点实验室自主研究项目(No.2011BWZ011)资助~~

摘　　要：以羧基改性的SBA-15(COOH/SBA-15)和钛酸四丁酯(TB)为原料,利用COOH/SBA-15表面上高分散的大量羧基将TB锚定,通过溶剂热处理得到高分散负载型TiO2/SBA-15催化剂.产物经XRD,Raman,FT-IR,TEM,N2吸脱附和UV-Vis表征,结果显示:所制备的TiO2/SBA-15催化剂为比表面大、结晶度较高的锐钛矿TiO2,TiO2均匀分散于SBA-15表面,此外,COOH/SBA-15有效抑制了TiO2晶粒的长大.以光催化还原CO2为探针反应,考察了TiO2/SBA-15催化剂在紫外光照射下的光催化性能.结果表明:相比于后处理浸渍法制备的光催化剂,本文制备的TiO2/SBA-15催化剂表现出了高的光催化还原CO2活性,主要产物为甲醇,且TiO2最佳负载量为16.5%,并对相关反应机理做了探讨.TiO2/SBA-15 catalysts, TiO2 nanoparticles well dispersed on SBA-15 supporter, have been successfully obtained through a self-assembly aging, carboxylation and subsequent solvothermal process. Firstly, P123 （PEG-PPG-PEG）, KC1, （2-cyanoethyl） triethoxysilane （CETES） and tetraethoxysilane （TEOS） were employed to form cyano-modified SBA-15 （CN/SBA-15） in 2.0 mol/L HC1 solution by self-assembly aging method. Secondly, carboxyl-modified SBA-15 （COOH/SBA-15） was got through carboxylation treatment in 48% H2SO4 solution at 95 ~C for 24 h. Finally, highly dispersed TiO2/SBA-15 catalysts were successfully synthesized via solvothermal method at 220 ~C for 12 h using COOH/SBA-15 and tetrabutyl titanate （TB） as raw materials. In order to remove the organic compounds and improve the crystallization of TiO2, the obtained TiO2/SBA-15 catalysts then were filtrated, washed by absolute ethanol for three times, dried at 80 ~C and cal- cined at 550 ~C for 4 h. Notably, the self-assembly and carboxylation process produced large number of good dispersive car- boxyl groups （COOH） on SBA-15, which could effectively anchored TB molecules on SBA-15 to promise the highly disper- sion Of TiO2 on SBA-15. The obtained TiO2/SBA-15 catalysts have been characterized by X-ray diffraction （XRD）, Raman spectrum, Fourier transform infrared spectroscopy （FT-IR）, transmission electron microscopy （TEM）, nitrogen adsorption and UV-Visible diffuse reflectance spectroscopy （UV-Vis）. Above results indicate that the TiO2/SBA-15 catalysts exhibit large specific surface area and TiO2 on SBA-15 supporter is anatase phase, they are both play important roles in photocata- lytic application. In the current manuscript, the photocatalytic reduction of CO2 under UV light irradiation as a prober reac- tion was used to investigate the photocatalytic performance of TiO2/SBA-15 catalysts. It was found that the obtained catalysts performed high photocatalytic capacity for CO2 reduction, especially when the loading amount of

关 键 词：羧基改性SBA-15 TIO2 光催化还原CO2 

分 类 号：O643.36[理学—物理化学]