We prepared a through-hole α-alumina membrane with a hierarchical porous structure from an anodic porous alumina membrane prepared using phosphoric acid electrolyte as the starting material. By heating the anodic porous alumina membrane to 1400 °C, aluminum phosphate nanoparticles were segregated in the α-alumina matrix at the anion-incorporated outer layer and the high-purity alumina layer forming a cell boundary band sintered as a high-density α-alumina layer at the central core of the pore wall. When the heat-treated membrane was immersed in concentrated hydrochloric acid, a unique hierarchical porous α-alumina membrane structure was formed with straight macropores and mesopores inside the pore wall due to the dissolution of aluminum phosphate nanoparticles. The developed α-alumina membrane can be ultimately used as a multifunctional filter because of its unique hierarchical porous structure and extremely high chemical and thermal durability.

我们从以磷酸电解质为起始原料制备的阳极多孔氧化铝膜制备了具有分层多孔结构的通孔α-氧化铝膜。通过将阳极多孔氧化铝膜加热到1400°C，磷酸铝纳米粒子在掺有阴离子的外层和高纯度氧化铝层的α-氧化铝基质中偏析，形成烧结成高密度α-的细胞边界带。孔壁中心的氧化铝层。当将热处理的膜浸入浓盐酸中时，由于磷酸铝纳米颗粒的溶解，形成了独特的分层多孔α-氧化铝膜结构，在孔壁内具有直的大孔和中孔。