Capillary Filling of Anodized Alumina Nanopore Arrays
Original entry: Caspar Floryan, APPHY 225, Fall 2010
K. J. Alvine, O. G. Shpyrko, P. S. Pershan, K. Shin, and T. P. Russell, Capillary Filling of Anodized Alumina Nanopore Arrays,Phys. Rev. Lett. 97, 175503 (2006).
Nanopores, Capillaries, Arrays, Filling
Nanopores have many applications in DNA translocation, nanofluidic transistors, nanoparticle self-assembly, catalysis and chemical sensors. It is thus important to understand the evolution of liquids in these pores.
This paper describes nanopore wetting experiments using the solvent perfluoro-methyl-cyclohexane and observed with small angle x-ray scattering. The pores are patterned in anodized alumina (aluminum trioxide) and are approximately 20nm in diameter. The experiments were carried out in an environmental chamber which allows precise control over the amount of solvent condensed inside the pores.
The pores were fabricated in a 1cm thick alumina membrane with a hexagonal pattern and nearest-neighbour spacing of approximately 58nm.
Absorption into pores was controlled by varying the chemical potential between the sample and the liquid using a thermal offset