...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Dalton transactions: An international journal of inorganic chemistry >Binuclear TiOMn charge-transfer chromophore in mesoporous silica
【24h】

Binuclear TiOMn charge-transfer chromophore in mesoporous silica

机译：介孔二氧化硅中的双核TiOMn电荷转移发色团

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

An all-inorganic heterobinuclear chromophore consisting of Ti~(IV) oxo-bridged to a Mn~(II) center has been assembled on the surface of silica pores of MCM-41 material. The key step of covalent attachmenton the pore surface is the reaction of a Mn~(II) precursor featuring weakly held CH,CN ligands with theOH group of a previously anchored titanol site. The optical diffuse reflectance spectrum reveals a —> TifflOMnin metal-to-metal charge-transfer (MMCT) absorption extending from the UVthroughout to visible into the red spectral region. FT-IR, FT-Raman and optical spectroscopy confirmthat the material is free of Mn oxide clusters, while EPR and Mn K-edge X-ray absorption spectraindicate that the donor center is predominantly in oxidation state +2. In situ FT-IR spectroscopyallowed detection of visible light-induced redox chemistry of the MMCT unit using 02 (1802) andmethanol as acceptor and donor probe molecules, respectively. Formate and water were observed asprimary products, with methyl formate emerging as a secondary condensation product. The observedphotochemistry demonstrates that excitation of the Ti'vOMn" —> TifflOMn"' results in completetransfer of an electron from donor to acceptor center, with the charge separation sufficiently long livedfor initiation of redox chemistry to occur. With donor and acceptor redox potentials appropriate fordriving multi-electron catalysts for water oxidation, proton or CO2 reduction, the TiOMn" unit is anattractive candidate as a charge-transfer chromophore in a solar fuel generating system.
机译：由Ti〜（IV）羰基桥连至Mn〜（II）中心的全无机异核双生色团已组装在MCM-41材料的二氧化硅孔表面。共价附着在孔表面上的关键步骤是Mn〜（II）前体的特征，该前体的特征在于保持不牢固的CH，CN配体与先前锚定的钛醇位点的OH基。光学漫反射光谱揭示了TifflOMnin金属到金属的电荷转移（MMCT）吸收，该吸收从UV延伸到可见光谱到红色光谱区域。 FT-IR，FT-Raman和光谱证实该材料不含Mn氧化物簇，而EPR和Mn K边缘X射线吸收光谱表明供体中心主要处于+2的氧化态。原位FT-IR光谱法允许分别使用02（1802）和甲醇作为受体和供体探针分子检测MMCT单元的可见光诱导的氧化还原化学。观察到甲酸盐和水为主要产物，而甲酸甲酯为第二缩合产物。观察到的光化学表明，Ti'vOMn”-> TifflOMn”的激发导致电子从供体完全转移到受体中心，并且电荷分离的寿命足够长，以引发氧化还原化学反应的发生。凭借适合驱动多电子催化剂进行水氧化，质子或CO2还原的供体和受体氧化还原电势，TiOMn“单元成为了太阳能发电系统中电荷转移生色团的诱人候选物。

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