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在298.15 K下采用现代微量热技术监测了微乳液法原位合成MnMoO4.H2O纳米棒过程中能量变化的微量热曲线.该曲线显示,反应开始瞬时放热,有一个尖锐的放热峰,在随后的过程中分别出现一个强的吸热峰和放热峰.通过X射线粉末衍射仪(XRD)、场发射扫描电子显微镜(FESEM)和透射电子显微镜(TEM)等对MnMoO.4H2O纳米棒的结构、形貌及尺寸进行了表征.结合微乳液的特性和量热曲线,讨论了MnMoO4.H2O纳米棒生长过程中的形貌演变和热动力学信息.整个生长过程包含微乳液的碰撞凝聚、反应成核、结晶和生长过程.经计算,反应成核过程、晶化过程及晶体二次生长过程的速率常数分别为6.35×10-3,7.18×10-4和9.16×10-5s-1.生长速率小于成核速率,这有利于纳米材料的形成.
The trace caloric curve of energy change during in-situ synthesis of MnMoO4.H2O nanorods by microemulsion method was monitored by the modern microcalorimetry at 298.15 K. The curve shows that the reaction begins to exotherm instantaneously with a sharp exothermic peak at A strong endothermic peak and an exothermic peak appeared in the subsequent process.According to XRD, FESEM and TEM, the thermal stability of MnMoO.4H2O nanorods Structure, morphology and size of MnMoO4.H2O nanocomposites were investigated.The morphological changes and thermodynamics information of MnMoO4.H2O nanorods were discussed in combination with the characteristics of microemulsion and calorimetry curves.The whole growth process includes collisional agglomeration of microemulsion, Reaction nucleation, crystallization and growth process.It is calculated that the rate constants of reaction nucleation, crystallization and secondary growth are 6.35 × 10-3, 7.18 × 10-4 and 9.16 × 10-5s-1, respectively The growth rate is less than the nucleation rate, which is conducive to the formation of nanomaterials.