A New technique was developed by MIT engineers based on uniting the principles of self-assembly and 3-D printing, using centimeter-high crystals, each made from billions of individual colloids about 1NM and 1MM which are defined as particles, this was also highlighted today in the Journal of Advanced Materials.
By this, Researchers found a way to print colloids such as polymer nanoparticles in highly arranged medium, similar to the atomic structures in crystals which can print structures, such as tiny towers and helices interfaces with light in specific ways depending on the size of the individual particles within each structure.
The team also says this 3-D printing technique is a new way to build self-assembled materials that leverage the novel properties of nanocrystals, at larger scales which can be implemented in optical sensors, color displays, and light-guided electronics that makes the device faster and more energy efficient
They also explain that if Uniformly sized colloidal particles are driven together via evaporation of their liquid solvent, causing them to assemble into ordered crystals, it creates structures that exhibit unique optical, chemical, and mechanical properties. The scientists had so far developed techniques to evaporate and assemble colloidal particles into thin films to form displays that filter light and create colors based on the size and arrangement of the individual particles which was now only limited to colloidal to thin films and other planar structures.
The team worked on colloidal printing techniques with the solutions of polystyrene particles in water, and created centimeter-high towers and helices containing 3billion particles where they experienced more exotic colloidal particles, namely silica and gold nanoparticles, which can exhibit unique optical and electronic properties and they also conducted tests on solutions containing different sizes of polystyrene particles to specify its relevant features.
Hart, the senior author of the paper mentions in a statement that, “For the first time, we’ve shown that it’s possible to build macroscale self-assembled colloidal materials, and we expect this technique can build any 3-D shape which we can implement to an incredible variety of materials”.
Alvin Tan, a graduate student in MIT’s Department of Materials Science and Engineering says that “There are a lot of things that can be performed using these kinds of particles ranging from conductive metal particles to semiconducting quantum dots. I think that would be very effective in fields including sensing, energy storage, and photonics.”