%0 Journal Article
%T <br>
%A 储伟
%A 周亚男
%A 敬方梨
%A 郭章龙
%A 高晓平
%J 物理化学学报
%D 2017
%R 10.3866/PKU.WHXB201611251
%X 采用水热法合成了含有89%{101}晶面的TiO2纳米锭(TiO2-101)和77%{001}晶面的TiO2纳米片(TiO2-001),将其用作载体来制备担载钯催化剂;研究了上述制备的TiO2纳米材料对Pd/TiO2-101和Pd/TiO2-001催化剂用于乙炔选择加氢制聚合级乙烯催化性能的影响.结果表明, Pd/TiO2-101催化剂表现出更好的乙炔转化率和乙烯收率.通过氢气程序升温脱附(H2-TPD)、氢气程序升温还原(H2-TPR)、透射电子显微镜(TEM)、CO化学吸附、X射线光电子能谱(XPS)和热重分析仪(TGA)等对催化剂进行了结构表征和分析.TEM和CO化学吸附结果表明, Pd纳米颗粒(NPs)在TiO2-101载体上有较小的颗粒尺寸(1.53 nm)和较高的分散度(15.95%);而Pd纳米颗粒在TiO2-001载体上的颗粒尺寸是4.36 nm和9.06%的分散度.Pd/TiO2-101催化剂上较小的Pd颗粒尺寸及其较高的分散度使催化剂具有更多的反应活性位点,这促进了其反应的催化活性.<br>Anatase TiO2 nanospindles containing 89% exposed {101} facets (TiO2-101) and nanosheets with 77% exposed {001} facets (TiO2-001) were hydrothermally synthesized and used as supports for Pd catalysts. The effects of the TiO2 materials on the catalytic performance of Pd/TiO2-101 and Pd/TiO2-001 catalysts were investigated in the selective hydrogenation of acetylene to polymer-grade ethylene. The Pd/TiO2-101 catalyst exhibited enhanced performance in terms of acetylene conversion and ethylene yield. To understand these effects, the catalysts were characterized by H2 temperature-programmed desorption (H2-TPD), H2 temperatureprogrammed reduction (H2-TPR), transmission electron microscopy (TEM), pulse CO chemisorption, X-ray photoelectron spectroscopy (XPS), and thermogravimetric analysis (TGA). The TEM and CO chemisorption results confirmed that Pd nanoparticles (NPs) on the TiO2-101 support had a smaller average particle size (1.53 nm) and a higher dispersion (15.95%) than those on the TiO2-001 support (average particle size of 4.36 nm and dispersion of 9.06%). The smaller particle size and higher dispersion of Pd on the Pd/TiO2-101 catalyst provided more reaction active sites, which contributed to the improved catalytic activity of this supported catalyst
%U http://www.whxb.pku.edu.cn/CN/Y2017/V33/I3/602