Prof. Serhii G. Nedilko is a Doctor of Science in Physics and Mathematics and Head of the R&D Laboratory “Spectroscopy of Condensed State of Matter” at Taras Shevchenko National University of Kyiv, Ukraine. His research focuses on advanced materials, nanocomposites, luminescent materials, optical spectroscopy, and nanotechnology. He has led numerous national and international research projects involving nanostructured composites, glass-ceramics, oxide materials, photoluminescent materials, and solar-energy-related materials. He has published more than 300 scientific papers and has an extensive record of international research collaborations and conference participation. His work includes the development and characterization of functional nanomaterials, luminescent ceramics, dielectric materials, carbon-based composites, and scintillation materials. He is also an inventor with several Ukrainian patents and has contributed to books and scientific monographs in materials science and nanotechnology. Prof. Nedilko is a member of professional scientific organizations, including the American Physical Society, Ukrainian Physical Society, and European Synchrotron Users Organization. His research has received recognition through national and international awards and research grants.

Interphase Layers in Dielectric Composites. Formation and Impact.                                                                                                                                                                                    A question of the interphase layers possible influence on the macro-properties of multiphase dielectric condensed media will be elucidated in the paper. It is known that the interphase layers can be formed at the phase boundaries in a solid material with a multiphase composition (e.g., in a composite). Here, we are talking about dielectric materials and also about the so-called mixed composites. That is that consisted of a matrix and micro/nano-sized filler particles incorporated into it. There can be several fillers, and they can be of different natures. For example, one filler is inorganic particles, and the other is organic. Thus in the case the material is called a “hybrid” composite. The composition, structure, interactions in these layers, and therefore the properties of the layers may differ from the properties of the components of the composite. It is obvious that the contribution of such layers to the macro-properties of the composite should increase with decreasing filler particle size. The report addresses the issues of interphase layers by presenting a brief review of the literature and describing the results of recent research conducted by the speaker's research team. We studied composites of various types: crystalline, glass-ceramic, polymer, and sol-gel. Both experimental (CEM, XRD, ASAXS, dilatometry, densitometry, microhardness measurements, calorimetry, thermogravimetry, optical spectroscopy – FTIR, Raman, luminescent) and theoretical and computational (computer-simulated) (MD, DFT) research methods were used. Considerable attention is paid in the report to the method of luminescent probing of the structure of multiphase composites developed by us. The method is based on a comparison of the characteristics of a luminescent probe, which is localized in the matrix, filler, and interphase layer. The possibility to manage the properties of the studied composites by controlling the contributions of interphase layers impact on their macro-characteristics is considered in the work.