Funding application supported

The project of our team "Comprehensive study of adsorbents based on hexagonal boron nitride nanoparticles for wastewater treatment of drugs" was supported by the Russian Science Foundation!

At present, the development of new drugs and their production has become a powerful branch of science and industry. Such growth of the pharmaceutical industry and widespread use of drugs inevitably leads to their release into the environment. In this regard, the search for effective techniques and new ways to remove antibiotics from water objects is currently an important scientific and practical task. The rapid development of nanotechnology, in particular the field of low-dimensional nanomaterials, can make a significant contribution to the development of this field and the improvement of the described situation. Adsorption of drug molecules onto a safe carrier is the most preferable purification methods, since they offer the possibility of using simple chemical-physical processes for cleaning water, air, surfaces from organic pollutants, which makes this process environmentally friendly and economical. Nanomaterials with a high specific surface area are ideal platforms for the development and production of cheap and highly effective biosensors, biofilters and carriers of antibacterial agents. These materials include hexagonal boron nitride (h-BN). This material has a unique set of properties: low specific density, high thermal and chemical stability, heat resistance, biocompatibility, good adsorption capacity, and a wide forbidden zone. Thus, nanostructured h-BN is an ideal candidate as an absorbent material. However, the adsorption efficiency on the perfect surface of hexagonal boron nitride is hampered by the small number of activated centers which requires its modification. The novelty of the project is to perform a systematic experimental-theoretical study and to obtain a general model of sorption/desorption of various antibacterial agents on the surface of modified boron nitride nanoparticles. The main objective of this project is to study the sorption and desorption processes of different types of antibiotics as applied to h-BN nanostructures by both theoretical and experimental methods. Such a systematic approach will allow to study in depth the process of sorption/desorption of antibiotics of different classes, to describe the type of binding of the analyte with the adsorbent, to determine the nature of sorption and to study its dependence on external conditions. Nanoparticles based on h-BN with different surface modifications (introducing defects, decorating with metal atoms and/or nanoparticles, introducing foreign atoms into the structure, etc.) will be studied. Various groups of antibiotics will be selected as analytes, including macrolides (erythromycin), sulfonamides (sulfamethoxazole), diaminopyrimidines (trimethoprim), aminoglycosides (ciprofloxacin), tetracyclines (tetracycline) and β-lactams (penicillin). Such a comprehensive study will eventually allow the production of effective adsorbents and membranes based on them for wastewater treatment from contamination by pharmaceuticals.

The project PI is Dr. Liubov Sorokina.

Funding application supported

Ultra-thin diamond films, diamanes, represent a diamond with a thickness of one unit cell. As a method for their preparation, the effect of a chemically induced phase transition was proposed, according to which multilayer graphene can be converted into a diamond film only under the action of chemical adsorption of adatoms on the surface (hydrogen, fluorine, etc.). We have studied the stability of diamanes and constructed a phase diagram of the transition of multilayer graphene to diamane depending on the thickness of the films and the type of surface.

A controlled tuning the structure of nanomaterials at the atomic level is the most important problem of modern materials science. Description of nanostructures stability requires to take into account their size and surface effects. This problem is especially clearly seen in the study of the phase transformation of nanomaterials, when the phase transition depends not only on external conditions, but also on the contribution of surface effects. For example, the classical Bundy’s carbon phase diagram changes with decreasing carbon film thickness, the graphite-diamond phase transition pressure increases, which reflects an increase in the instability of diamond with size reduction. Upon reaching the atomic thickness, diamond films should demonstrate a number of extremely attractive physical properties, but their synthesis requires fundamentally different approach. Two ways of synthesis of nanomaterial usually considered: the “top-down” and “bottom-up” approaches. The top-down paradigm, when macroscopic material is separated to the required nanostructure probably is not the case, since it is impossible to obtain diamond films of nanometer thickness by separating the bulk diamond. The bottom-up approach (the required nanostructure is synthesized from smaller nanostructures) seems to be the most relevant for this case, although it certainly requires overcoming a number of non-trivial scientific problems. The traditional method of chemical vapor deposition is not applicable for solving the problem of obtaining diamond films of atomic thickness due to the high growth rate and their imperfection at the atomic level. In this project, we will consider another option for producing diamond films, when the initial material is not gas, but a bilayer graphene film. Their formation occurs through a controlled chemical reaction of two graphene sheets with reference atoms, mainly hydrogen and fluorine. We will try this method in an experiment, and we will study theoretically in details the mechanism of transformation of graphene layers not only in the case of bilayer graphene, but also other structures based on weakly coupled layers, double-walled carbon nanotubes and other related nanomaterials.

The project PI is Dr. habil. Pavel Sorokin.

Funding application supported

The international project of our team "Ion-implanted two-dimensional materials for single-atom catalysis" was supported by the Russian Foundation for Basic Research in the framework of the international project ERA.Net RUS plus RUS_ST2019-327

Single atom catalysis, involving isolated metal atoms supported by the appropriate substrates, is one of the most innovative and rapidly developing research areas, which can be referred to as the ultimate limit of downsizing from the nanoparticles traditionally used in heterogeneous catalysis. In spite in the considerable recent progress, further developments in both fields have been hindered by the drawbacks of the chemical methods traditionally used to produce the relevant materials, e.g., atom/particle agglomeration and their incorporation into the bulk of substrate material. At the same time, the recent progress in the synthesis of various nanostructures with a high surface-to-volume ratio, which are the ideal supports for single-atom catalysts, and successes in the controlled low-energy ion implantation open unique opportunities in this area for further development of low-cost and highly efficient hybrid systems. One of the most advanced nanostructured materials with a high specific surface includes h-BN and g-CN. The development of highly effective single atom catalysts (SAC) based on them using transition metals opens up wide opportunities for the study and development of one of the most innovative areas at the junction between materials science and catalysis in recent years, single atomic catalysis on nanostructures. In this project, by combining advanced physical and chemical experimental approaches and extensive multi-scale atomistic simulations, we plan to produce and study in details new SAC. Specifically, we plan to synthesize h-BN and g-CN nanomaterials, hydrogenate, fluorinate and chlorinate them and control they defective structure in order to tune substrates sorption characteristics. The most effective SAC synthesis schemes based on modified h-BN and g-CN will be determined and a comprehensive estimation of their catalytic characteristics in reactions of great fundamental and practical importance will be carried out: oxidation of carbon monoxide and methane reforming. Using theoretical simulation methods, we will study the features of the electronic structure of SAC, their adsorption properties, as well as energy barriers in the studied chemical reactions.

The main results of the project would include mastering of a technique for new nanomaterials fabrication, low-energy ion implantation, getting fundamental microscopic understanding of their atomic structure, electronic and catalytic properties, finding optimum metal atoms for specific catalytic reactions using theoretical simulations and experimental search.

This project will be carried out through the efforts of our team, as well as our colleagues from NITU MISIS (Laboratory of Inorganic Nanomaterials). The project is headed by Dr. Pavel Sorokin. On the German side, the project is headed by Prof. Stefan Faksko (Helmholtz Center Dresden-Rossendorf, Dresden), on the Greek side by Prof. Konstantinos Triantaphyllidis (Aristotle University of Thessaloniki, Thessaloniki)