偏钒酸铵在空气中热分解产物形貌的演变

以偏钒酸铵(NH_4VO_3)在空气中热分解的热重-差热(TG-DSC)分析为依据,利用X射线衍射仪(XRD)和扫描电镜(SEM)分析了偏钒酸铵在空气中热分解最终产物的物相和偏钒酸铵在空气中升温到DSC曲线不同拐点温度分解产物的形貌。研究发现,偏钒酸铵在空气中热分解有两个阶段,第一阶段出现了中间相(NH_4)_2O·2V_2O_5,第二阶段出现了热分解产物由无定形状态转变成晶体的过程。偏钒酸铵在空气中不同阶段下热分解产物的形貌基本上是不规则的片状,但是最终产物V_2O_5的厚度较均匀。

Morphology Evolution of Pyrolysis Products of Ammonium Metavanadate in Air

Based on the TG-DSC analysis for the thermal decomposition of ammonium metavanadate (NH4 VO3,AMV for abbreviation) in air,The phases of the final products for the thermal decomposition of AMV in air and the morphologies of the pyrolysis products of AMV at the inflection point temperatures in corresponding DSC curve were characterized by X-ray diffraction (XRD) and scanning electron microscope (SEM),respectively.The results show that there are two steps in the thermal decomposition process of AMV in air.There is (NH4)2O · 2V2O5 as mediate phase during the first step,and the transition from amorphous to crystal state of the pyrolysis products of AMV in air happens in the second step.The morphologies of the pyrolysis products of AMV in air are mainly irregular flakes in different periods,but the thickness of vanadium pentoxide (V2O5) is relatively homogeneous.