Injection rate control on the growth direction in chemical gardens

Area of Science:

• Materials Science
• Chemical Engineering
• Biomimetics

Background:

• Spontaneous organization of inorganic structures is key for biomimetic material design.
• Understanding self-assembly mechanisms is crucial for creating advanced materials.

Purpose of the Study:

• To investigate the controlled spontaneous organization of tubular precipitation structures.
• To determine the factors influencing the growth direction of these inorganic structures.
• To establish principles for autonomous material growth mimicking biological systems.

Main Methods:

• Utilized an upright Hele-Shaw cell for controlled reactions.
• Injected aqueous copper chloride into aqueous sodium silicate solutions.
• Varied the injection rate to observe effects on tubular structure growth direction.

Main Results:

• Tubular precipitation structures were successfully formed.
• The direction of tube growth (upward or lateral) was dependent on the injection rate.
• Identified key factors influencing growth direction, including injection rate, water penetration, and density differences.

Conclusions:

• Demonstrated control over inorganic spontaneous organization through injection rate manipulation.
• Provided insights into the mechanism of growth direction selection and bifurcation.
• Opened avenues for designing materials with autonomous growth capabilities, inspired by biological vascular formation.