| 超细AgO粉末：制备及热分解非等温动力学 |
| Ultrafine Silver Peroxides: Preparation and Non-isothermal Kinetics of Thermal Decomposition |
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| 摘要: 采用化学沉淀法，以臭氧为氧化剂制备了超细AgO粉末，并用XRD、XPS、SEM和粒度分析仪对制备的粉末进行了表征，借助热重分析法(TG)和线性升温理论对超细AgO粉末的热分解过程和非等温热分解动力学机理进行了研究。结果表明，制备的AgO属于单斜晶系，形貌为片状，其粒径分布在45~551 nm之间，大部分在200 nm左右；AgO的热分解分两步，158 ℃开始分解，放出氧气形成Ag2O，413 ℃进一步分解形成Ag；其热分解反应服从核生成和核成长为控制步骤的A2机理，热分解表观活化能为90.26 kJ·mol-1，反应频率因子为1.64×108 s-1。 |
| 关键词: AgO 热分解 动力学 反应机理 |
| 基金项目: |
| Abstract: Ultrafine silver peroxide powders were prepared by chemical precipitation method using ozone as oxidant and characterized by X-ray diffraction, X-ray photoelectron spectroscopy, scanning electron microscope and particle size analyzer. The process and kinetic behavior of thermal decomposition of ultrafine silver peroxide powders were studied by means of thermogravimetry and linear temperature theory. The results show that the prepared silver peroxide belongs to monoclinic system. The particle size is distributed in the range of 45~551 nm with a flake morphology and the most probable distribution is around 200 nm. The decomposition of silver peroxide is in two steps. First decomposition begins at 158 ℃ and silver oxide is formed by oxygen evolution. Further decomposition into silver begins at 413 ℃. The decomposition reaction obeys random nucleation and subsequent growth mechanism(A2) with an apparent activation energy of 90.26 kJ·mol-1 and a reaction frequency factor of 1.64×108 s-1. |
| Keywords: silver peroxide thermal decomposition kinetics reaction mechanism |
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| 摘要点击次数: 1729 |
| 全文下载次数: 2003 |
| 沈文宁,冯拉俊,孔珍珍,冯 慧.超细AgO粉末：制备及热分解非等温动力学[J].无机化学学报,2010,26(9):1577-1582. |
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