Abstract
The Liesegang phenomenon can be used for micro- and nanofabrication processes to yield materials with periodic precipitation of diverse types of materials. Although there have been several attempts to control the periodicity of the Liesegang patterns, it remains unclear whether the periodic precipitation of AgCl in gel medium causes regular- or revert-type patterns. To confirm the periodicity of the AgCl pattern, we conduct one-dimensional experiments under various ion concentration conditions. From microscopic observations, three different precipitation modes were observed, i.e., continuous precipitation with a sharp front, periodic precipitation and continuous precipitation with a gradual front. For these three modes, numerical analyses of the pattern geometry are performed for the periodic precipitation. It was confirmed that the regular-type pattern appeared for all concentration conditions conducted in the present experiments. Furthermore, the pattern was found to obey the spacing law and the Matalon–Packter law. From our experiments, we concluded that AgCl forms regular-type Liesegang patterns, regardless of the dimension of diffusion.
Highlights
The spontaneous formation of spatiotemporally periodic structures is an essential aspect that can be seen in nature and sometimes gives rise to a variety of functions in the field of micro- and nanotechnology [1]
We conducted pattern-formation experiments using 1D test tubes under various concentration conditions using an AgNO3 aqueous solution and gelatin gel doped with NaCl
The present results indicate that AgCl is a regular type, in 2D systems [31] and in 1D systems
Summary
The spontaneous formation of spatiotemporally periodic structures is an essential aspect that can be seen in nature and sometimes gives rise to a variety of functions in the field of micro- and nanotechnology [1]. There appear to be two possibilities that could change the pattern geometry from the revert-type of AgI and AgBr to the regular-type of AgCl: (i) the difference in the concentration gradient of silver ions and (ii) differences in the preferential adsorption to the colloidal particles. This issue can be clarified to carry out experiments on AgCl pattern formation in 1D systems For this purpose, we conducted pattern-formation experiments using 1D test tubes under various concentration conditions using an AgNO3 aqueous solution and gelatin gel doped with NaCl. To eliminate the effect of light, all experiments were performed in the dark, unless otherwise stated. An attempt was made to confirm the validity of the Matalon–Packter law for the observed periodic structures
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
