About the achievement

Metal halide perovskites (MHP) are materials that have unique physicochemical properties: a high light absorption coefficient or the possibility to modulate their properties in a desired direction through controlled defects in their crystal lattice. This has made MHPs one of the most intensively developed groups of semiconductors in the last decade. The main driver behind the development of MHP chemistry was their use in perovskite solar cells (PSCs), which are considered by many scientists to be the most important achievement in the field of photovoltaics since the invention of silicon cells. Perovskite photovoltaics offer the possibility of using cells that are not only efficient and cheap to manufacture, but also lightweight, thin and flexible. However, the use of perovskite materials themselves is much wider and also includes photocatalysis, light-emitting diodes (LEDs) and ionizing radiation detectors.

MHPs are usually produced in laboratories using classic wet chemistry methods that require the use of organic solvents. However, this approach is associated with significant problems, including those related to the production of a limited MHP palette resulting from the inability to use insoluble substrates, as well as the instability of the resulting colloidal dispersions.

Prof. Janusz Lewiński and his team proposed an alternative, pioneering approach in which MHPs are synthesized in a simple and efficient way using a solvent-free mechanochemical method, i.e. through a direct, mechanically induced reaction of substrates in solid form.

This approach provides greater reproducibility of the synthesis process and the possibility of using more substrates, and thus the possibility of obtaining perovskites that are not available in the wet chemistry process. In addition, the mechanochemically obtained perovskite materials (so-called mechanoperovskites) are highly stable in an inert atmosphere.

Moreover, photovoltaic cells manufactured using mechanoperovskites have better efficiency and longer lifetime, which is thanks to fewer structural defects. These very beneficial functional properties of mechanoperovskites developed by Prof. Lewiński’s team have been confirmed in cooperation with leading foreign research laboratories involved in the production of perovskite solar cells. What’s equally important is that the developed solvent-free mechanochemical synthesis methods are characterized by reduced environmental costs, including – in particular – high atom and energy efficiency, which is in line with the growing importance of the “green chemistry” trend. It is in this context that mechanochemistry is included in the list of “10 innovations that will change the world” announced by the International Union of Pure and Applied Chemistry (IUPAC).

The new mechanochemical method for the synthesis of perovskites opens the way to their wider practical use, and also provides a convenient platform for the implementation of industrial production of perovskite solar cells and the potential replacement of silicon photovoltaic devices commonly used today.

About the laureate

Prof. Janusz Lewiński is the head of both the Division of Catalysis and Organometallic Chemistry at the Faculty of Chemistry of the Warsaw University of Technology (since 2014) and the “Coordination Complexes and Functional Materials” Group at the Institute of Physical Chemistry of the Polish Academy of Sciences.

He is one of the pioneers of the revival of mechanochemistry as an extremely effective and ecological method of synthesizing chemical compounds and obtaining functional materials.

He has co-led two large EU projects (FP7 Noblesse and H2020 FET-Open GOTSolar). He has also managed over 20 scientific projects financed by the most important Polish research-funding institutions: the Foundation for Polish Science (including two TEAM projects) and the National Science Centre (including two MAESTRO grants).

Prof. Lewiński combines basic and applied research, which is reflected in over 20 patents of which he is the author or co-author. In 2016, he founded Nanoxo, a company involved in the development of chemistry and technology of nanometric forms of semiconductors, the so-called quantum dots, containing no heavy metals or perovskite materials.

The research conducted by Prof. Lewiński is multidisciplinary. His interests include fundamental inorganic and organometallic chemistry, as well as catalysis, chemistry and engineering of functional materials and nanomaterials, and nanotechnology. A characteristic feature of the research conducted by his team is the implementation of basic research at the molecular level for practical applications in the production of functional materials.

About the prize

The Prize of the Foundation for Polish Science (FNP) is regarded as the most important scientific distinction in Poland. It is even called the Polish Nobel Prize. It is an individual prize, awarded by the Foundation Council following a competition. The winners are selected from a group of candidates nominated by eminent representatives of the scientific community, invited by name by the FNP Council and Executive Board. The FNP Council acts as the Competition Committee and selects the winners based on the opinions of independent experts and reviewers – mainly from abroad – who assess the candidates’ achievements. The prize is awarded in four areas: life and earth sciences, chemical and materials sciences, mathematical-physical and engineering sciences, and humanities and social sciences.

Source: Fundacja na rzecz Nauki Polskiej