KFU shows advancements in obtaining perovskites for 3D printing

A paper was published in Additive Manufacturing.

Perovskites are of great interest to the scientific community due to their high photoluminescence quantum yield (over 90 percent), narrow emission band (less than 50 nm), and tunable emission spectra across the entire visible spectrum.

The rapidly developing field of additive manufacturing technologies is in constant search for new functional materials. The use of promising perovskite nanomaterials in such technologies is hindered by their instability under environmental conditions.

Project lead, Lead Research Associate of the Laboratory of Prospective Carbon Nanomaterials Ayrat Dimiev, explains, "On the one hand, our research is fundamental, on the other hand, it has applied value. Perovskites are a class of compounds that are very fashionable in the modern scientific world, as they have unique photoluminescent properties, but they have one drawback—they are not stable under normal conditions. The humidity of the air mercilessly destroys them, which leads to the loss of luminescent properties. To prevent this, various works are being carried out to stabilize them. One of the proposed methods is the encapsulation of perovskites in a protective material—glass or polymer—i.e. their isolation from external conditions. However, no significant progress has yet been made along this path."

The know-how of KFU scientists lies in a new method for manufacturing a polypropylene/perovskite quantum dot composite in one stage by co-extrusion of reagents for the synthesis of perovskite with polypropylene. Perovskite quantum dots are formed in situ and uniformly distributed in the polymer matrix. The finished material exhibits a high quantum yield and unparalleled stability under ambient conditions.

"Synthesis of perovskites occurs directly in the extruder, where the polymer is loaded to draw the thread. Previously, the process of obtaining such composites included a number of labor-intensive stages: starting with the rather complex synthesis of perovskites themselves with their isolation and purification, and ending with the subsequent multistage and labor-intensive introduction of perovskites into a polymer. The last stage included the dissolution of the polymer in an organic solvent and its subsequent distillation. In our method, the composite is synthesized in one step and 'in one glass' in full accordance with the principles of green chemistry and sustainable development. The resulting composite has high heat and moisture resistance, can be directly used for 3D printing by FDM at a temperature of 200-220 degrees under ambient conditions. The developed method is simple, has virtually no waste, and is scalable indefinitely," continues Dimiev. "Phosphors used today in LEDs contain expensive rare earth metals such as yttrium and cerium, but we offer another material that is cheaper and more efficient. Perovskites are also relevant for photovoltaics; in laboratory samples, the highest photoelectric conversion coefficient today is achieved using perovskites."

The study was carried out with funds allocated by Kazan Federal University for the development of the project "Materials for Green Energy and Life Support". The synthesis of perovskites in organic solvents and their characterization by X-ray diffraction were supported by the Russian Science Foundation.

More information:
High-throughput, low-cost and "green" production method for highly stable polypropylene/perovskite composites, applicable in 3D printing
www.sciencedirect.com/science/ … ii/S2214860422004845

Provided by Kazan Federal University