钨酸锌微纳米材料的水热合成及发光性能研究

Hydrothermal Synthesis and Luminescence Properties of ZnWO_4 Micro-nanomaterials

以Zn（NO3）2·6H_2O和Na_2WO_4·2H_2O为原料，草酸为沉淀剂，采用水热法在180℃反应4h制备了ZnWO_4粉体，并考察了前驱体溶液pH值对ZnWO_4发光性能的影响。通过X射线衍射（XRD），场发射扫描电子显微镜（SEM）和荧光光谱（PL）等测试手段对样品的物相、微观形貌和发光性能进行表征。结果表明：pH值为7～9时适宜合成ZnWO_4粉体，pH=7、8时，得到的是星状结构ZnWO_4粉体；pH=9时分别得到的是由长度为500nm，直径为100nm的纳米棒交叉组装而成的镂空结构ZnWO_4粉体。相比之下，由纳米棒交叉组装而成的镂空片的发光性能最佳。

Using Na_2WO_4·2H_2O and Zn（NO3） 2· 6H_2O as raw materials, oxalic acid as precipitator, the powders of ZnWO_4 were synthesized via the hydrothermal method. The effects of the precursor solution pH value （pH = 6,7,8,9 and 10） on the luminescence properties of ZnWO_4 powders were examined. The phase compositions, morphologies and luminescence properties of the powders were characterized by XRD, SEM and PL measurements. The results indicate that the pH value of 7-9 could favor the synthesis of ZnWO_4 powders. The pure-phase ZnWO_4 powders with star-like morphology can be obtained when the pH is 7 and 8, while hollowed-out shaped ZnWO_4 powders self-assembled by a length of 500 nm, diameter of 100 nm nanorods were synthesized when the pH is 9. In contrast, the hollowed-out shaped ZnWO_4 powders synthesized at pH value of 9 possessed the best luminescence properties.