【摘要】 以三缺位Keggin型硅钨酸盐为前驱体,采用化学沉淀法成功合成出2例新型纳米材料M₃SiW₉（M=Cu.,Co.）。其中,Cu₃SiW₉表现为新颖的纳米晶须形貌,Co₃SiW₉表现为尺寸均一的球形纳米颗粒。经过一系列控制实验证明,通过掺杂不同类型的金属离子可以调控M₃SiW₉的形貌。我们对产生该现象的机理进行了合理推测。此外,使用荧光素钠作为掺杂剂可使Cu₃SiW₉纳米晶须具有优良的光致发光性能,测试表明,多酸并未淬灭荧光素钠的发光,复合材料在510 nm具有明显的发射波长。最后,我们对Cu₃SiW₉纳米晶须负载CdS量子点后的光催化产氢性质进行了研究。结果表明,当Cu₃SiW₉与CdS的质量比为1∶1时,复合材料的产氢效率约为纯CdS量子点的10倍。这也证实多金属氧酸盐的存在可以有效抑制CdS量子点光生电子与空穴的复合,从而大幅提高其光解水产氢的效率。更多还原

【Abstract】 Two novel nano-materials M₃SiW₉（M=Cu.,Co.）based on polyoxometalate have been successfully syn-thesized by chemical precipitation method using trivacant Keggin-type silicotungstate as precursor.Cu₃SiW₉exhibit-ed extremely rare nanowhisker morphology in polyoxometalate-based nano-materials and Co₃SiW₉simultaneously showed uniform nanosphere morphology.Control experiments were implemented to indicate the morphologies of M₃SiW₉could be tuned by doping different transition metals.Furthermore,fluorescein sodium was employed as dop-ant to endow nanowhiskers with an emission peak at 510 nm.Moreover,the nanowhiskers were also used as carriers to combine with CdS quantum dots to improve the photocatalytic property.The results show that when the mass ratio of Cu₃SiW₉to CdS was 1∶1,the hydrogen production efficiency of the composite was about 10 times that of pure CdS quantum dots.This also confirms that the presence of polyoxometalate can effectively inhibit the recombination of CdS quantum dot photogenerated electrons and holes,thereby greatly improving the efficiency of photolysis of water to produce hydrogen.更多还原