Phys.org December 17, 2021
Researchers in the Netherlands have demonstrated that by illuminating a solution of barium carbonate and silicon with UV light they can control when and which structures arise at the micrometer scale. As soon as barium carbonate crystals form in the solution, the silicon joins in and precipitates together with the crystals, thus giving rise to the unusual shapes. A tiny bit of CO2 gas in the solution starts this process. If one could ensure that CO2 arises at the exact location and time desired, this would result in an on-off switch for the chemical reaction. Using this approach they constructed a helix and a coral close to each other, simply by moving the ray of light slightly and making a minor adjustment to the chemical reaction. Very large number of crystals can be produced next to each other in a pattern. They succeeded in converting the crystals into semiconductors. The work may lead to less expensive way to make semiconductors…read more. Open Access TECHNICAL ARTICLEÂ
Concept of light-controlled generation of local gradients. Credit: Advanced Materials, 01 December 2021Â