一维铌酸钠纳米杆的合成及光催化性能

摘要

以Nb2O5、NaOH为起始物，NaOH为矿化剂，通过传统水热法并结合后期热处理，成功制备了高结晶度、生长完善的一维正交相NaNbO 3纳米结构。采用TG-DSC、XRD和SEM对不同阶段产物的组成、结晶结构、形貌进行了表征。将所制备的Na2Nb2O6·1.4H2O前驱样品在不同温度下热处理，当温度高于400℃时可以转变为一维的正交相NaNbO 3纳米杆。随着热处理温度的升高，产物的结晶性保持良好，但其形貌开始发生扭曲甚至出现裂纹。另外，对不同后处理的样品进行光催化产氢测试，结果表明随着热处理温度的增大，一维铌酸钠纳米材料的光催化活性先增大后降低，当后热处理温度为400℃时，平均的产氢率可达104.5μmol·h–1。%High crystalline and well-grown 1D orthorhombic phase NaNbO3 nanostructure was successfully prepared by traditional hydrothermal method with Nb2O5, NaOH as the source of niobium and sodium, and NaOH as the mineralizer,respectively. TG-DSC, XRD and SEM were employed to investigate the composition, crystalline structure and morphology of products at different stages. The Na2Nb2O6·1.4H2O precursors were calcined at different temperatures. And they can be easily converted into 1D orthorhombic phase NaNbO3 nanorods when the temperature is above 400℃. As the temperature is increased gradually, the products keep good crystallinity, but start to distort in morphology even broke with defects. In addition, the photocatalytic activity was also evaluated by H2 production rate for the products after different post-treatment conditions. It was found that the photocatalytic activity of the products increase at the beginning and decrease at the end. When the post-heat treatment condition is 400℃ for 2 h, the average hydrogen production rate over NaNbO3 nanorods is 104.5μmol·h−1.