Evaporation induced self-assembly of zeolite - A micropatterns due to the stick-slip dynamics of contact line

Abstract

In this study, a new surfactant-solvent system was described for the preparation of periodic stripe patterns of zeolite A on solid substrates. The evaporation induced self-assembly of zeolite A particles was due to the stick-slip dynamics of the three-phase contact line of the colloid solutions in acetone containing 10% (v/v) poly(dimethylsiloxane) (PDMS) fluid (2 est.). In order to investigate the possible effects of particle size and the particle concentration on the stick-slip dynamics, three types of zeolite A samples with different particle sizes (zeolite A-1: 250-500 rim, zeolite A-II: 100-250 nm and zeolite A-III: 0-100 nin) were utilized to prepare 0.007-0.06% (w/v) colloidal dispersions. Zeolite A micropatterns were self-assembled on the surface of glass, high density polyethylene (HDPE) and poly(tetrafluoroethylene) (PTFE) substrates, which were placed vertically inside the colloid solutions and held against the wall of the cylindrical vial during the evaporation of acetone. The stripe patterns of zeolite A particles were analyzed with field emission scanning electron microscope (FE-SEM) and optical microscope. The widths of microstripes and the distance between the stripes were found as 2-20 mu m and 40-60 mu m respectively depending on the particle concentration. By using the stick-slip dynamics of colloids, the linear micropatterns of zeolite A nanocrystals were prepared with low cost and low energy. (c) 2007 Elsevier B.V. All rights reserved.