Syntheses of Lanthanide-containing Polyoxotungstates Substituted by Transitionmetal-Nonmetal pairs : Its Developments for Photo-electron Molecular Catalysts

2000年：用双钒离子[LnV2W8]取代镧系十钨酸盐的合成进行了各种尝试。然后，用硅烷剂将所得的LnV2W8固定在氧化钛-氢氧化物[TiO(OH)2]上。初步考察了LnW10对碳氢化合物的光催化氧化作用，并比较了加入不同过渡金属离子对LnW10光催化活性的影响。2001年：尝试用有机基团[org-LnV2W8]对LnV2W10进行改性，并将LnV2W8和org-LnV2W8进一步固定在先前用硅烷剂[si - tio2]改性的TiO(OH)2上，得到了LnV2W8/si - tio2和org-LnV2W8/si - tio2催化剂。采用FT-IR、UV-vis、ICP、ESR等方法对样品进行了分析。1) LnV2W8对烃类h2o2氧化的催化活性随着v2取代物的加入而显著增强；对甲基硫化物、2-己烯-1-醇和薄荷醇的活性分别提高了约4倍、3倍和2倍。特别是org-LnV2W8/si - tio2催化剂在有机无溶剂体系中表现出优异的h2o2氧化碳氢化合物的活性，从绿色催化剂化学的角度来看是非常合适的。2)在紫外光照射下对org-GdV2W8/si - tio2进行esr测量；比较了Gd（III）、V（IV）和Ti（III）在TiO2上随电子转移的esr信号强度的变化，并对引入有机气体后的变化进行了研究。3)目前正在测量紫外-可见光谱和荧光光谱的变化以及强度的变化。4)尝试用钒和硅醇基同时取代LnW10，合成新的LnW10样品，并将其固定在si - tio2上。5) LnW10与Cu（II）和Cu(II)+Pd（II）离子结合，光催化氧化醇类化合物的活性显著增强。

In 2000 : Synthesis of lanthanide decatungstates substituted by two-vanadium ions[LnV2W8] have been variously attempted. Further, LnV2W8 thus obtained was tried to fix on titanium-oxide-hydroxides[TiO(OH)2] with silane agents. Photocatalytic oxidation of hydrocarbons were examined prelininarly on LnW10, and effects of various transition metal ions added to LnW10 on the photocatalytic activities were compared, as previously reported. In 2001 : Modification of LnV2W10 with organic group[org-LnV2W8] and further fixzation of LnV2W8 and org-LnV2W8 on TiO(OH)2 modified previously with silane agents[sil-TiO2] were attempted variously to obtain LnV2W8/sil-TiO2 and org-LnV2W8/sil-TiO2 catalysts. Those samples were successfully analyzed by FT-IR,UV-vis,ICP,ESR, so on. 1)The catalytic activities of LnV2W8 for H2O2-oxidation of hydrocarbons were greatly enhanced with the V2-substitution, LnV2W8 ; the activities for methyl-sulfide, 2-hexene-1-ol, and menthol increased ca.4-times,3-times, and 2-times, respectively. Especially, org-LnV2W8/sil-TiO2 catalyst showed an excellent activity for H2O2-oxidation of hydrocarbons in an organic solvent free system, being very suitable from a viewpoint of green catalyst chemistry. 2)ESR-measurements of org-GdV2W8/sil-TiO2 were taken place under UV-light irradiation ; changes in the intensities of ESR-signals among Gd(III),V(IV), and Ti(III) on TiO2,accompanied with an electron-transfer, were compared and also those changes were examined under introducing organic gasses. 3)Measurements of variations in UV-vis and fluorescence spectra, accompanied with the changes in the intensities, are now in progress. 4)Syntheses of new LnW10 samples as substituted simultaneously by vanadium and silanol-groups, and their fixzation on sil-TiO2 have been attempted. 5)Photo-catalytic activities of LnW10 were enhanced greatly in the combination with Cu(II) and Cu(II)+Pd(II) ions, for instance, for photo-catalytic oxidation of alcohols.