纳米铁酸锌的冲击波合成及它的光催化活性

 利用溶液共沉淀法制备了纳米氧化锌和三氧化二铁的非常均匀的混合物。通过常规的高温焙烧法和冲击波压缩方法分别合成了铁酸锌。这两种铁酸锌对硫化氢气体的光催化脱氢表现出显著不同的催化活性。试验表明：高温焙烧法合成的铁酸锌是一种颗粒度为几十纳米的结晶完整的化合物；而冲击波合成的铁酸锌是一种颗粒度为几个纳米的非化学计量比化合物，它的光催化活性随着冲击波合成压力的增高而迅速提高。在37 GPa时，冲击波合成的铁酸锌对H₂S脱氢的光催化活性要比高温焙烧法制备的铁酸锌高出3倍以上。利用粉末X光衍射，透射电镜及电子衍射，Mossbauer谱等分析手段对这两种铁酸锌的晶格结构、细观特征及磁特性进行了表征。

SHOCK SYNTHESIS OF ZINC FERRITE AND ITS PHOTOCATALYTIC ACTIVITY IN DEHYDROGENATION OF H 2S

Zinc ferrite fine powders were synthesized from a very uniform mixture of nanometer zinc oxide and nanometer ferric oxide powders, by using shock compression techniques up to pressures 37 GPa, or by conventional high temperature calcination at 700 ℃ for 10 h. Both types of samples were used as a photo-catalyst in the dehydrogenation of H₂S. Results show that shock synthesized zinc ferrite exhibits much higher photo catalytic activity and is a factor of 3 larger than that of the calcinated, which increase with the shock pressures under which the catalyst was synthesized. In contrast, photo catalytic activity of single component catalyst of ZnO and Fe₂O₃ decreases as the shock conditioning pressure increases. Characteristics of the XRD patterns of shock synthesized zinc ferrite along with its TEM features and Mossbauer spectra indicate that the enhancement in catalytic activity of photo-dehydrogenation may be attributed to the formation of the very fine and highly non-stoichiometric zinc ferrite during shock synthesis processing.