P. Sarkisov International Laboratory of
Glass-Based Functional Materials
 

 D. Mendeleyev University of Chemical Technology of Russia
 English   

Preliminary results and perpectives of activity of the Laboratory in 2010-2012

In two years, since its foundation, the activity at the International Laboratory of Glass-Based Functional Materials (ILG) has concerned a multiplicity of actions, aimed at grounding and assessing all the characteristics a world-level laboratory must possess to have prolonged competitiveness in materials science research and good perspectives of impact on technology and innovation. Specifically, ILG actions have included:

  1. implementation of technological equipment for the production of advanced materials, extending the activity up to pre-industrial scale,
  2. installation of top-level scientific instrumentation for the investigation of functional properties of materials,
  3. training of young people for the formation of skilled personnel in the field of scientific and technological research,
  4. creation of a network of international collaborations with recognized research centers all around the world,
  5. know-how transfer and knowledge exchange through a mobility program involving training of young members of the team in foreign laboratories and attendance at scientific conferences,
  6. technology transfer of scientific results to industry and creation of spin off activities.

The targets above have produced different kinds of relevant concrete outcomes that constitute reliable indicators of project development and laboratory assessment: these outcomes comprise:

  • high-impact scientific achievements, testified by publications in high-ranked international scientific journals,
  • patents on applicative ideas of technological transfer,
  • establishment of spin-off activity for the production of glass-based devices,
  • communications at international conferences,
  • training exchanges, joint investigations, collaborative meetings, visits of experts.

As a matter of fact, the ILG laboratory is now integrated into a broad international network of world-class laboratories. Within this network, Russian and foreign scientists of recognized high reputation gave their qualified and valuable contribution for the development of the ILG as a modern international laboratory. Here I would like to particularly mention the deputy head of the ILG prof. V.N. Sigaev for his restless action of coordination, as well as prof. G.E. Malashkevich (Institute of Physics, Belarus), Dr. S.Yu. Stefanovich (L.Ya. Karpov Scientific-Research Institute of Physical Chemistry), the director of International Institute "New Functionality in Glass" prof. H. Jain (Lehigh University, USA), prof. T. Komatsu (Nagaoka University of Technology, Japan), and prof. E. Fargin (University of Bordeaux, France). However, the most important peculiarity of the ILG team, as planned in the original project, is that about 70% of the personnel is composed by young Russian researchers, students, and postgraduate students, most of them from the hosting Mendeleyev University. Really, the most valuable outcome is doubtlessly the creation of an operative research center including, besides world-class infrastructures, a skilled and efficient team, trained in collaborative world-level research activity, able to give a real perspective of development and sustainability of the operative potential at ILG also in the future.

Thanks to this potential, the ILG team has achieved, since the laboratory foundation, a multiplicity of scientific and technological results in different directions of glass science. It is useful to summarize some of these achievements just to give an idea of the different research lines at ILG.

  1. 1. In the field of functional materials for optical technology, the ILG team developed in a short time new types of laser glasses, magnetooptical and electrooptical glass-based materials, and light-emitting nanostructured glasses for UV-visible and near-IR applications. Additional and transversal research lines have been carried out on thermal and laser-assisted glass nanostructuring mechanisms, crucially important for engineering optical materials. The investigated processes include the formation of local structures and patterns at the surface or in the bulk of glass, providing nonlinear optical response or light-emission properties embedded in micro- or nanoregions of the glass matrix. These lines, belonging to frontier research, are important for the development of integrated optics and optical computer technology, enabling the fabrication of nanostructured luminescent fibers, microsized integrated waveguide lasers, and electrooptic transducers. Importantly, the opportunity of investigating functional properties on optical quality glass samples produced by the ILG itself provides a fundamental advantage over research groups from other countries.
  2. In the field of glass-based materials for biomedical applications, the ILG team has reached a leadership position as the first and the only Russian developer and manufacturer of glassy microspheres for internal radiotherapy of oncological diseases. At present, microsphere production at ILG is able to fully satisfy the demand of Russian country in this type of radioactive drugs, nowadays widely used in the West (at a cost of about 20000$ per operation). The development of this research line gives also the know-how for the fabrication of microspheres with innovative composition and various radioactive characteristics, studying also possible composite core-shell structures. Studies have also been carried out in the field of biomaterials for bone implantology, identifying new promising compositions of phosphate-based porous glassceramics for crystallization controlled porosity.
  3. Investigations at ILG also regarded radiotransparent high-temperature glassceramics and related composites for aircraft technology, including superhigh-speed aircrafts. The development of this kind of materials has been implemented in the Scientific and Production Enterprise "Technology", Obninsk.
  4. The ILG activity also concerned the implementation of a specific technology for the fabrication of high-strength radiation-resistant glass film for thermal control coatings of solar batteries and control systems of spacecrafts. Ground and flight tests have been successfully conducted. It is planned to implement large scale production of this glass films for the needs of Lavochkin scientific-production association and "Thais" company.

The development of these lines of technology innovation was accompanied, as expected in frontier research, by significant knowledge advance, as testified by publications in high impact scientific journals. I would like here to briefly mention just four examples of scientific achievements obtained during the ILG activity, representative of the fruitful relation between technology innovation and scientific knowledge advance:

  1. The development of new yttrium aluminosilicate microspheres for radio-therapy included thestudy of microsphere variants with core-shell structure. In these innovative microsystems, yttrium-depleted surface layers was created by selective etching, so as to reduce the risk of 90Y release into the organism. Importantly, the spectroscopic study of the structural transformation on micrometer scale clarified that the high degree of structural reconstruction of the glass network depends on mechanisms driven by non-bridging oxygen sites during hydroxylation and glass reconstruction. The analysis gave important insight into open fundamental questions - recently approached by molecular dynamics - about the short-range structure and the chemical stability of this class of glass, important also in photonics and nuclear waste disposal.
  2. The investigation of new light-emitting glassy materials for broadband infrared amplification in optical communication systems brought the ILG team to study the mechanisms of near-infrared light-emission of nickel ions in novel nanostructured germanosilicates with gallium oxide nanoparticles. The investigation clarified the role of Ni ions in promoting nanophase crystallization without affecting nanoparticle size and concentration, also demonstrating that all Ni ions can be totally embedded into the nanophase. The obtained data gave the basis for designing composition and doping so as to keep the ion-ion distance above values below which non-radiative decay processes become predominant, enabling the incorporation of several Ni ions per nanoparticle without too large a worsening of the light-emission efficiency.
  3. The identification of a strategy for the production of innovative high-temperature resistant and radio-transparent glassceramics for aircraft technology was directed towards the investigation of Sr-anorthite containing composites. The study of Sr-anorthite crystallization in SrO-Al2O3-TiO2-SiO2 composites was approached through the identification of the crystalline phases accompanying the thermally activated partial devitrification of the glass, and the role of aluminum in forcing the crystallization of Ti-Al-oxide against TiO2 segregation. Finally, a clear indication was found of the importance of the SrO/Al2O3 ratio in the determination of adequate characteristics of thermomechanical resistance and radio-transparency.
  4. The embedding of homogeneous dispersions of gold nanoparticles in bulk optical glass was analyzed as a function of post-synthesis thermal treatment in controlled temperature gradient. The results gave important indication on the mechanisms of coalescence of small clusters of gold atoms in glass, and now enable an unprecedented control of metal nanoparticle size for applications in photonics and sensoristics.

The achievements above are the result of the implementation of two types of facilities: 1) efficient and unique equipments for the production of advanced materials and 2) top-level instrumentation for the investigation of physical and chemical properties and mechanisms related to innovative material functionalities.

As regards the implemented technological equipments for material production, ILG facilities includes four main pre-industrial complexes:
   - Melting and fabrication of high quality glass and nanostructured glass for optical applications,
   - Melting and fabrication of sealing glasses and other low-temperature glasses,
   - Fabrication of glassy microspheres for nuclear medicine by means of plasma torch technology,
   - Production of radiation-resistant glass films by glass drawing process from melt.

On the other hand, the optimization of material functions strictly depends on the availability of adequate characterization techniques, so as to efficiently obtain indication of the relations between structure, composition, and physical properties, and to enable investigation of innovative physical mechanisms in nanostructured systems. During two years, the project has succeeded in implementing world class laboratories for material investigations along six main experimental directions with toplevel instrumentation:
   - Laser-ablation atomic spectroscopy for the identification of glass composition, composition inhomogeneity, and contaminants, extended to light elements,
   - Differential scanning calorimetry for the study of glass transition and crystallization, up to 1500 K temperature,
   - Micro-Raman spectrometer coupled to atomic-force-microscope for the investigation of material structures and micro-patterning generated by laser-induced nanostructuring,
   - X-ray diffraction analysis for the identification of crystalline phase and nanophase formation in glass matrices,
   - Optical absorption and photoluminescence spectrophotometer from UV to medium-IR for the study of intrinsic and extrinsic light-emission and attenuation properties of optical glasses,
   - Pulsed femtosecond IR laser for experiments of controlled laser-assisted glass nanostructuring and characterization of second and third order optical nonlinearity.

The implementation of the new technological and scientific facilities at ILG enables in two years to achieve relevant results with a real innovative potential, even because of the prompt response of the young team and the positive effects of training within the activated network of international collaborations. Applicative outcomes of ILG activity include:

  • patented neodymium laser glass,
  • nanostructured glass possessing broadband NIR luminescence for a new generation of optical amplifiers,
  • optical glass with wide-band-gap nanoparticles for UV-to-visible conversion for large scale production of low-cost deep-UV viewers,
  • magneto-optical glass with superior characteristics with respect to previous technology in the world,
  • pilot-scale production of glass microspheres for nuclear medicine, unique for Russia
  • high-temperature glass and glass ceramics composites for the aircraft and spacecraft industry,
  • radiation-resistant glass film, produced by a drawing line, mainly for demands of the Federal Space agency of the Russian Federation.

Such positive and promising development of the ILG activity in the last two years underwent verifications within the scientific community and within the network of collaborations, obtaining valuable unbiased advices about its progress. As a matter of fact, at the end of these two years, the high level of technological and scientific potential at ILG, including its team, is recognized by well-known foreign experts in the field of glass: Professor H. Jain (Lehigh University, USA), Professor T. Komatsu (Nagaoka University of Technology, Japan), Professor E. Fargin (Institute of solid state chemistry of Bordeaux, France), Professor B. Champagnon (University Lyon-1, France), Professor P. Pernice (University of Naples, Italy), the Director of the Institute of Biomaterials (Erlangen-Nuremberg, Germany), Prof. A. Boccaccini and others, with whom long-term bilateral and multilateral scientific collaborations are established. The chairman of the Education Committee of the State Duma of the Russian Federation, Professor A. Degtyarev, visited the laboratory in May 2012 and gave a positive reference to the ILG. The director of the International Institute "New Functionality in Glass" at the University of Lehigh (USA), Prof. H. Jain, after his visit in June 2012 agreed to include the ILG in the international network of research laboratories, covering more than 30 countries, so allowing the participation of students and postgraduate students in conferences, training courses, extension courses with funding by International Institute programs.

As regards the effects the ILG foundation had on the educational system, a valuable synergy between the Laboratory and the hosting university took place. On the one hand, the university considerably supported the ILG creation: after the starting Rector's order in 2011, an additional order in January 2012 provided a total area of 324 m2 for the ILG activity. On the other hand, the ILG activity considerably impacted on the organization of the Mendeleyev University, which underwent a structural transformation, merging the Department of Chemical Technology of Silicates and the Department of Inorganic Chemistry in the Department of Technology of Inorganic Substances and High-Temperature Materials, in which the ILG plays a key role as research and innovation centre. General practical training courses at ILG facilities will be established for graduate students, and high performance equipment will be used for the needs of the whole university, primarily for researchers in the field of inorganic chemistry, significantly increasing the capabilities of D. Mendeleyev University Collective Use Center. Furthermore, the shared use of ILG facilities has been also the occasion to introduce a general principle, widespread in the West in the assignment of beam time and grants for experiments at high-tech equipment. According to this principle, ILG users are asked to report about the obtained scientific results, and further applications are accepted only if applicants present reports on previous experiments including published or accepted publications. Thus, all practical student works (coursework, diploma work) and even more the works of postgraduate students (if they require ILG tools) are now necessarily aimed at the production of original and publishable research results. This approach helps to involve students in real scientific research and to develop highly qualified professionals. So, the ILG has become a valuable educational resource for students, providing them an opportunity unique for Russia to participate in world class scientific and technological works and to get a real practical knowledge of melting and forming of special glasses, experimentally studying functional properties in advanced glass, nanostructured glasses, and microshaped glasses for medicine.

As a matter of fact, the main actions expected from the ILG - concerning scientific and technological research, formation of human capital, training for high-level education, know-how transfer and knowledge exchange within international collaborations, technological transfer - are now activated and in full progress. Importantly, these actions concern a polyphony of works, which follows naturally from the multiplicity of aims related to the wide variety of applications of glass-based materials. As a result, the laboratory is now a single fast-developing organism, which in a few years will be able to constitute a self-maintaining research centre with good perspectives of sustainability - even without Government support - and with a real impact on the country. This conclusion is supported by the fact that all sections of the project plan, carried out by different groups at ILG, are aimed at solving concrete problems through new solutions, giving also good perspectives of innovation and leadership of Russia in different fields of materials science.

To summarize in few indicators, the ILG - now occupying a total area of 324 m2 - is able to carry on world class research, combining scientific studies with specific actions devoted to the commercialization of the products of own intellectual property. More than 10 patents applications have been submitted by the ILG. Scientific articles submitted by members of the ILG, as a rule, are published in journals with high impact factor, with a resulting mean impact factor (2.5) higher than the planned one. At present, there are 13 postgraduate students and 9 students in the laboratory team (excluding students who are involved on coursework and diploma work using the ILG facilities). More than 20 specialists per year have been retrained. Seven PhD theses were prepared by ILG researchers.

Finally, an important indicator of success in a research activity is the opening of new promising lines of development and investigation as a result of the performed activity. At the end of the project, the presently activated lines of investigation are opening important applicative developments and perspectives of frontier research at ILG. I would like to remark the following ones:

  • The creation of glass-ceramics with working temperature up to 1250 gives now the possibility to investigate innovative composites characterized by even higher working temperature, with high potential for the development of domestic aircraft and spacecraft industry.
  • The development at the ILG of the first pilot-production line in Russia for manufacturing glassy microspheres for nuclear medicine can be extended to innovative variants - based on different radionuclides and alternative glass matrices with enhanced biocompatibility - so as to initiate a new medical branch for the treatment of oncological diseases by means of brachytherapy in Russia.
  • The fabrication of radiation-resistant glass films with electrochromic properties and enhanced durability with respect to those currently applied in space solar panels opens the way to a complete re-equipment of photovoltaic cells manufacturing.
  • Optical glass melting and laser-assisted engineering lines at the ILG - applied to glasses and nanostructured glasses for light-emitting devices and electrooptical systems - will enable the development of new materials for optical technology. The small-scale characteristics of the pilot production lines, with a significant miniaturization and energy saving, can meet the demands of the domestic optical instrument engineering in new, non-standardized multi-function optical materials. As a matter of fact, a specific initiative has already been organized for the technology transfer of the abovementioned research lines to product commercialization, through the creation of a small innovative company "Steklon" as a part of the laboratory.
  • The experience on nanostructured glasses with embedded gold nanoclusters and the potential reached at ILG in the spectroscopic analysis of the mechanisms of light-emission of optically active ions in glass can now be merged to design novel optical sensors - based on plasmonics - with unprecedented sensitivity for bio-analysis and diagnostics. The possibility of embedding metal nanoparticles with controlled and graduated size in glass suitable for optical components - together with the possibility of doping with light-emitting rare earth ions with stringent resonance excitation conditions - opens the way to new strategies for the detection of very-low amount of biomolecules.
  • The knowledge advance in the mechanism of nanocrystallization of oxides in glass puts the ILG in a leadership position in the field on nanostructured glasses with wide-band gap nanoparticles and nonlinear nanophases in optical materials, potentially suitable for the design of novel systems for optical transparent electric and electro-optical devices. In fact, the possibility of producing controlled nanoparticle patterns inside the glass by direct laser-writing can enable the production of complex optical, electrical, and electro-optical multifunctional materials.