Seeing the cocatalyst boosted vectorial charge transfer on a single photocatalyst particle

Seeing the cocatalyst boosted vectorial charge transfer on a single photocatalyst particl

Identifying the pieces of puzzles in the very early stages of zeolite formation process:an UV Raman spectroscopic study

Identifying the pieces of puzzles in the very early stages of zeolite formation process:an UV Raman spectroscopic stud

Visualizing the photogenerated charge carriers at the surface of single particle photocatalyst

Visualizing the photogenerated charge carriers at the surface of single particle photocatalys

Visualizing the photogenerated charge separation on single crystal Cu2O photocatalyst

Visualizing the photogenerated charge separation on single crystal Cu2O photocatalys

Surfaceimaging of photoinduced charge seperationon single particle photocatalyst

Surfaceimaging of photoinduced charge seperationon single particle photocatalys

UV resonance Raman spectroscopic identification of different

TS-1 is an active and selective catalyst in a number of oxidation reactions with H2O2 under mild conditions. Generally, the tetrahedral titanium in the framework of TS-1 are thought to be the active sites for selective oxidation[1]. In this work, UV resonance Raman spectroscopy was used to study the different titanium species in TS-1 synthesized under different conditions. Figure 1 shows the Raman spectra of TS-1 synthesized at different pH values excited with 266 nm (A)and 244 nm laser(B). Besides the Raman bands of zeolite framework at 290 cm-1, 380 cm-1,800 cm-1, the spectra also show Raman bands at 490 cm-1, 530 cm-1, 960 cm-1 and 1125 cm-1which arise from the framework Ti-O-Si species. With lowering of the pH value of the synthsis gel, a new Raman band at 695 cm-1 appeared and became stronger. At the same time,the Raman band at 1125 cm-1 which come from the framework titanium increased obviously. The results demonstrate that the titanium species in TS-1 are different when the pH value of the synthsis gel was changed. The different titanium species may play distinctive roles during the catalytic reactions. Highly active and selective TS-1 could be synthesized if the titanium species were controlled uniformly according to different reactions.TS-1 is an active and selective catalyst in a number of oxidation reactions with H2O2 under mild conditions. Generally, the tetrahedral titanium in the framework of TS-1 are thought to be the active sites for selective oxidation[1]. In this work, UV resonance Raman spectroscopy was used to study the different titanium species in TS-1 synthesized under different conditions. Figure 1 shows the Raman spectra of TS-1 synthesized at different pH values excited with 266 nm (A)and 244 nm laser(B). Besides the Raman bands of zeolite framework at 290 cm-1, 380 cm-1,800 cm-1, the spectra also show Raman bands at 490 cm-1, 530 cm-1, 960 cm-1 and 1125 cm-1which arise from the framework Ti-O-Si species. With lowering of the pH value of the synthsis gel, a new Raman band at 695 cm-1 appeared and became stronger. At the same time,the Raman band at 1125 cm-1 which come from the framework titanium increased obviously. The results demonstrate that the titanium species in TS-1 are different when the pH value of the synthsis gel was changed. The different titanium species may play distinctive roles during the catalytic reactions. Highly active and selective TS-1 could be synthesized if the titanium species were controlled uniformly according to different reactions

An aitificial photosynthetic system containing an inorganic semiconductor and a molecular catalyst for photocatalytic water oxdation

An aitificial photosynthetic system containing an inorganic semiconductor and a molecular catalyst for photocatalytic water oxdatio

AM-6分子筛的快速合成及原子线形成机理研究

报道了一种4 h快速合成AM-6分子筛的方法,考察了凝胶中K＋含量和起始凝胶碱度对AM-6分子筛纯度以及晶化度的影响.结果表明,向合成体系中引入适量K＋可以抑制杂相的生成,在n（K＋）/n（V4＋）=3和pH=12.5条件下,制备的样品为纯相且晶化度最高.结合紫外-可见吸收光谱和紫外拉曼光谱研究了AM-6分子筛的形成过程.结果表明,在合成初期形成了由VO4四面体共角相连的VO 3-的链状结构,该结构是形成AM-6分子筛中—V—O—V—原子线的重要中间物种