...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>The journal of physical chemistry, C. Nanomaterials and interfaces >Tuning the Acid/Base and Structural Properties of Titanate-Loaded Mesoporous Silica by Grafting of Zinc Oxide
【24h】

Tuning the Acid/Base and Structural Properties of Titanate-Loaded Mesoporous Silica by Grafting of Zinc Oxide

机译：通过接枝氧化锌来调节钛酸酯负载介孔二氧化硅的酸/碱和结构性质

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Mesoporous silica (SBA-15) loaded with TiO2. species was synthesized by anhydrous grafting of titanium isopropoxide, and a novel procedure for the preparation of ZnO_x/SBA-15 materials by grafting of Zn(acac)2 was explored. The TiO_x/SBA-15 and ZnO_x/SBA-15 materials as well as subsequently prepared bifunctional ZnO^- and TiO_x-containing SBA-15 materials were characterized in depth by combining N2 physisorption measurements, UV-vis, X-ray photoelectron and X-ray absorption spectroscopy, and CO2 and NH3 temperature-programmed desorption experiments. The characterization results confirmed a close proximity of ZnO_x and TiO_x in the subsequently grafted materials. Because of strong interactions between the Zn precursor and the SiO2 surface, the order of the ZnO_x and TiO_x grafting steps affected the amount of Ti-O-Zn bonds formed in the materials. When ZnO_x is present in SBA-15, subsequently grafted TiO_x is higher coordinated and more Ti-O-Zn bonds are formed compared to SBA-15 in which TiO_x was introduced first, indicating strong interactions between the Ti precursor and ZnO_x. While all TiO_x, and ZnO_x-containing samples exhibit a large amount of acidic sites, ZnO_x present as isolated species or small clusters in SBA-15 significantly improves the CO2 adsorption capacity by introducing basic sites. In the subsequently grafted samples the amount of acidic and basic sites is found to be unaffected by the order in which the two transition metals are introduced.
机译：负载有TiO2的中孔二氧化硅（SBA-15）。通过异丙醇钛的无水接枝合成了该物种，并探索了通过接枝Zn（acac）2制备ZnO_x / SBA-15材料的新方法。通过结合N2物理吸附测量，紫外可见光，X射线光电子和X射线对TiO_x / SBA-15和ZnO_x / SBA-15材料以及随后制备的含ZnO2和TiO_x的双功能SBA-15材料进行了深度表征射线吸收光谱，以及CO2和NH3程序升温脱附实验。表征结果证实了随后接枝的材料中ZnO_x和TiO_x非常接近。由于Zn前驱体和SiO2表面之间的强相互作用，ZnO_x和TiO_x接枝步骤的顺序会影响材料中形成的Ti-O-Zn键的数量。当SBA-15中存在ZnO_x时，与先引入TiO_x的SBA-15相比，随后接枝的TiO_x的配位更高，并形成更多的Ti-O-Zn键，表明Ti前驱体与ZnO_x之间存在强相互作用。尽管所有TiO_x和含ZnO_x的样品均显示大量酸性位点，但SBA-15中作为分离物种或小簇存在的ZnO_x通过引入碱性位点显着提高了CO2吸附能力。在随后接枝的样品中，发现酸性和碱性位点的数量不受两种过渡金属引入顺序的影响。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号