AAO模板受热失重及发光机理的研究

Investigations on the Thermal Weight Loss and the Photoluminescence Mechanism of AAO Template

为了深入理解草酸溶液中制备的阳极氧化铝（AAO）模板受热失重以及草酸根对模板发光性能的影响,利用程序升温脱附与质谱联用（TPD-MS）、热重分析（TGA）、差热分析（DTA）以及光致发光（PL）等技术对AAO模板进行了系统研究.热失重分析结果表明,当温度低于402.2℃时,发生H2O、CO以及CO2分子的脱附以及掺杂草酸的分解,其中H2O的脱附为失重的主要原因;在402.2-866.7℃范围内,主要是草酸盐分解放出CO和CO2引起失重,CO为主要产物;碳酸盐以及残余的草酸盐的剧烈分解发生在866.7~1022.9℃范围内,主要放出CO2,并且引起大量失重.由热重结果及脱附产物中CO的摩尔比得到草酸根残余量随处理温度的变化趋势.最后,对模板PL强度、草酸根含量以及氧空位缺陷（F＋）浓度三者随处理温度的变化趋势进行了关联,对AAO模板发光的原因进行了分析.

In order to deeply understand the influence of oxalic impurities on the optical properties of anodic aluminum oxide（AAO）,AAOs prepared in oxalic acid solution were investigated by the temperature programmed desorption combined with mass spectrograph（TPD-MS）,thermogravimetric analysis（TGA）,differential thermal analysis（DTA） and photoluminescence（PL） techniques.The thermal weight loss of AAOs was monitored in the temperature range between room temperature（RT） and 1200℃ and analyzed quantitatively.The analysis results indicate that the desorption of H 2 O,CO and CO 2 molecules and the decomposition of oxalic acid impurity occur below 402.2℃,therein water desorption is the main reason for the weight loss.In the temperature range of 402.2 866.7℃,the incomplete decomposition of aluminum oxalate occurs and gives birth to CO and CO 2 with CO as the major component.The drastic decomposition of aluminum carbonate and oxalate take place in the temperature range of 866.7 1022.9℃,CO 2 is the main product.According to the TGA results and the molar ratios of CO in the desorption products,the content variation of oxalic impurities intermingled in bulk AAOs is obtained with the change of temperature.At last,the correlation of the optical property for AAOs with the concentration of oxalic impurities and oxygen vacancies（F ＋） is proposed.