摘要
二次阳极氧化法制备纳米多孔氧化铝由于其应用范围广、制备工艺简单、制备成本低廉等因素被广泛采用,但对制备过程中纳米有序多孔结构的形成机理研究存在较多分歧。根据电解液在电场和温差作用下内部出现的有序环流,结合二次阳极氧化法制备多孔氧化铝的实验过程和样品的形貌表征,对有序多孔结构的形成机理进行了研究。结果表明:在阳极氧化铝形成初期,致密氧化铝膜表面导电离子浓度在外电场作用下发生变化,电解液中形成有序分布的粒子环流,是该阶段影响一次阳极氧化铝膜有序结构形成的主要因素;阳极氧化后期,电解液作为远离平衡态的开放系统,在达到临界温度时进入有序的耗散结构状态,即电解液中出现了自组织的热对流,是二次阳极氧化能够形成大孔径、高度有序多孔结构的主导因素。
Two-step anodizing process has been widely adopted in the fabrication of nanoporous porous anodic alumina(PAA)due to its wide application,simple preparation technology and low cost.However,there have been different viewpoints on the formation mechanism of PAA during the two-step anodizing process.According to the fact that electrolyte has internal orderly circulation affected by electric field and temperature difference and considering the experiment of the fabrication of PAA by two-step anodizing oxidation method and the appearance of the samples,the formation mechanism of ordered porous structure was researched.The results manifest that ordered porous anodic alumina is attributed to orderly circulation of electrolyte in the preliminary stage of PAA formation process,which is caused by the difference of conductive ion concentration under the effect electric field on the surface of compact alumina film.In the later period of anodizing,the electrolyte,as an open system away from the equilibrium state,enters an ordered dissipative structure state when the critical temperature is reached.That is,self-organized thermal convection occurs in the electrolyte,which is the dominant factor that the secondary anodizing can form large pores and highly ordered pores structure.
作者
谢宁
塔力哈尔.夏依木拉提
汪超
XIE Ning;TALGAR·Shaymurat;WANG Chao(Basic Department,Xinjiang Institute of Engineering,Urumchi 830023,China)
出处
《电子元件与材料》
CAS
CSCD
北大核心
2018年第4期44-48,共5页
Electronic Components And Materials
基金
新疆工程学院科研基金项目(2014xgy031612)
高层次引进人才工程资助项目(2015RST011712)
关键词
阳极氧化铝
自组织
有序多孔结构
粒子环流
贝纳尔对流
耗散结构
anodized aluminum
self-organized
ordered porous structure
particle circulation
Bénard convection
dissipative structure
