Home https://server7.kproxy.com/servlet/redirect.srv/sruj/smyrwpoii/p2/ Science https://server7.kproxy.com/servlet/redirect.srv/sruj/smyrwpoii/p2/ The chemical experiment produces the brightest fluorescent materials ever made

The chemical experiment produces the brightest fluorescent materials ever made



The world has a new brightest fluorescent material and it is the first of its kind. Instead of trying to improve fluorescent molecules, a team of chemists has developed a new material that preserves the optical properties of fluorescent dyes.

This effectively prevents one of the biggest problems in the production of fluorescent materials – the tendency of fluorescent dyes to fade and change color when they solidify from a liquid. And the work is not done just for fun.

“These materials have potential application in any technology that requires bright fluorescence or requires the design of optical properties, including solar energy collection, bioimaging and lasers,”

; said chemist Amar Flood of Indiana University.

“Beyond that, there are interesting applications that include converting light to capture more of the solar spectrum in solar cells, light-shifting materials used to store information and photochromic glass, and circularly polarized luminescence that can be used in 3D technology. display. “

Fluorescent molecules absorb light and then emit it again at longer waves with lower energy. Found far beyond the markers you used in school notes, they have many practical applications, from fluorescent biomarkers in cell research to OLED screen technology.

However, of the more than 100,000 fluorescent dyes developed to date, almost none can be mixed predictably and reliably; the creation of solid fluorescent materials is just as challenging. When dyes are converted to solids, they tend to fade (dim the brightness), their colors change, and their quantum efficiency deteriorates.

Chemists do not understand why this happens. This is a well-understood phenomenon called exciton binding. When dyes are converted to a solid, they are packaged close together, which causes them to bond.

The optical changes that occur during this coupling are difficult to predict, but it is safe to say that the reliable transfer of the optical properties of a fluorescent liquid to a solid is very difficult to do.

fluorescent hands3D printed shapes with the new material. (Flood of Amar)

“The problem with hardening and bonding the dye occurs when the dyes stand side by side inside the solids,” Flood said. “They can’t help but touch each other. Like little children sitting through the story, they interfere with each other and stop behaving like individuals.”

So, the team developed a solution to the problem based on the separation of fluorescent molecules. They took a colorless solution of macrocyclic molecules called cyanostares and mixed them with the fluorescent dye.

This use of macrocycles – a large class of ring molecules – is not a new idea, and others have tried it before. But the big difference is that these earlier experiments were used colored macrocycles.

As their new solution dried, it formed what the team called Small Molecular Ion Isolation Grids (SMILES), which effectively kept dye molecules separated from each other, preventing them from interacting and preserving their optical properties with high accuracy.

“Some people think that colorless macrocycles are unattractive, but they have allowed the insulation grille to fully express the bright fluorescence of the dyes unencumbered by the colors of the macrocycles,” Floud said.

comparison of fluoroNew materials under white light (left) and UV light (right). (Flood of Amar)

This material can then be taken in several directions. Can be grown in crystals; may form a dry powder; or can be incorporated directly into polymers. The researchers found that it worked perfectly with several commercially available fluorescent dyes, which they said in their article “marked these materials as plug and play.”

This means that any currently available fluorescent dye must work on the team’s macrocycle solution shelf to produce a superbly shiny, hard material that accurately retains the properties of the liquid dye.

But we still have work to do before we get to this point. The first step was to develop the material. Now the team has to study it.

“These materials are brand new, so we don’t know which of their innate properties will actually offer superior functionality,” Floud said.

“We also don’t know the boundaries of materials. So, we will develop a fundamental understanding of how they work, providing a stable set of design rules for creating new properties. It’s crucial for these materials in the hands of others – we want continue to search for crowds and work with others in this effort. “

The study was published in Cell Press,,


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