The Department Head– Kuchmiy Stepan Yaroslavovych

 Corresponding Member of the National Academy of Sciences of Ukraine

 Doctor of Chemistry, Professor

e-mail: kuchmiy@inphyschem-nas.kiev.ua stephan@ukr.net

Brief summary of the Department of Photochemistry

The department of photochemistry was organized in 1934 and headed by Prof. Borys Yakovych Dain (department head till 1971) – a student of  L. V. Pisarzhevskii- Academician of the USSR Academy of Sciences. B.Ya. Dain initiated expe¬rimental studies of the photoinduced electron transfer which is a fundamental primary step in the natural photosynthesis and many photo¬che-mical redox-reactions. These studies were continued in the works of the Dain’s pupils – Yosyp Yosypovych Dilung (Nominee of the State Award of Ukraine in the field of Science and Technology and L.V. Pisarzhevsksii Award of the National Academy of Sciences of Ukraine, Doctor of Scien¬ces, Profes¬sor, Head of the Department of photochemistry in 1971–1993), who studied the photoinduced electron transfer phenomena in the systems based on chlorophil, dyes and aromatic chromophores, and Anatoliy Ivanovych Kryukov (Nominee of the L.V. Pisarzhevsksii Award of the National Academy of Sciences of Ukraine, Doctor of Sciences, Professor, Head of the Laboratory  of photochemistry of coordination compounds, later – Laboratory of the photocatalytic reactions, 1974–1993), who established a vital role of the photoinduced electron transfer in the photochemistry of metal complexes and in photocatalysis, both homogeneous, with the participation  of coordination compounds, and in heterogeneous, in the presence of semiconductor crystallites. Since 1993, the department has been headed by Kuchmiy Stepan Yaroslavovych (Laureate of the LV Pisarzhevsky Prize of the National Academy of Sciences of Ukraine, Doctor of Chemical Sciences, Professor, Corresponding Member of the National Academy of Sciences of Ukraine).

Employees of the department, July 2016

From left to right: O.S. Kutsenko, O.E. Raevskaya, A.V. Korzhak, V.M. Granchak, A.V. Kozytsky, S.Ya. Kuchmiy, V.V. Shvalagin, O.L. Stroyuk, N.S. Andryushina, Ya.V. Panasyuk, O.P. Rozovik, G. Y. Grodziuk.

Research mainstreams

• • fundamental and applied aspects of photophysical, photochemical and photocatalytic processes in light-sensitive systems comprising novel materials – nanometer semiconductor crystals, graphene oxide and reduced graphene oxide, various nanosized heterostructures and composites;
• • new ways to efficient materials for photo- and electroluminescence, photovoltaics, non-linear optical materials based on polymer materials, semiconductor and metal nanocrystals, and dyes;
• • development of light-sensitive materials for applications in printing, electronic and other industries.

Recent most important result

Principles of rational design of efficient photocatalytic systems based on semiconductor crystals, electron transfer mediators, sensitizers and secondary catalysts were formulated. Data on origins of the quantum size effects in highly disperse semiconductors and their influence on the photophysical, photochemical and photocatalytic properties of semiconductor nanocrystals and nanostructures were summarized. Fundamentals of a new trend in the semiconductor photochemistry named nanophotocatalysis were created. Common features and principal differences between classic semiconductor photocatalysis and nanophotocatalysis were analysed and shown to originate from spatial exciton confinement in semiconductor nanocrystals

New methods of synthesis of quantum dots of cadmium chalcogenides (~ 2 nm in size) stabilized by amine-containing polymers and mixed copper-indium sulfides and silver-indium stabilized by mercaptoacetate ions have been developed. The formed nanoparticles are characterized by photoluminescence in the visible range of the spectrum with high quantum yields, the color of which can be smoothly controlled by changing their composition and synthesis conditions.  

Photoluminescence spectra and photographs of colloidal solutions of Ag-In-S nanoparticles obtained in glycerol at Ag: In = 1: 4 immediately after synthesis (1) and after heat treatment at 120° C for 5 (2), 10 (3), 15 (4), 20 (5), 25 (6), 30 (7), 35 (8) and 40 min (9).

New electrochemical and photocatalytic methods were applied to prepare ITO/ZnO/CdS and ZnO/CuxS heterostructures exhibiting a much higher photoelectrochemical activity than similar films produced by conventional methods.

Scanning electronic microscopy images of nanoheterostructures ZnO/CdS (a) and ZnO/CuxS (b). (c) Volt-ampere curve of the solar cell: photoanode – ZnO/CdS, counter electrode – ZnO/CuxS, electrolyte – aqueous solution of 0.5 M Na2S. (isc – photocurrent density; Voc – open circuit photopotential; FF – volt-ampere curve filling factor; η – light energy conversion efficiency).

Nanocomposites of titanium dioxide with bimetallic particles of copper and gold – TiO2/Au/Cu and TiO2/Ag/Cu were obtained, which at the optimal ratio of components show much higher activity in the reaction of photocatalytic reduction of CO2 with water vapor to methane than monometallic Au/Ag and TiO2/Cu.

(а) Dependences of CH4 formation rates in the process of photocatalytic reduction of CO2 on the composition of metal components of TiO2/Au/Cu (1) and TiO2/Ag/Cu (2) composites (a). Scanning electronic microscopy images of TiO2/Au/Cu (b) and TiO2/Ag /Cu (в)..

New photocurable polymerization compositions were developed that found applications in technologies of protective masks for printed electronic plates production, UV-light curable varnishes and protective coating for printing industry.

Scientific collaborations

The department conducts joint research with a number of research centers in Ukraine (Institute of Semiconductor Physics of the NAS of Ukraine, Institute of Macromolecular Chemistry of the NAS of Ukraine, Taras Shevchenko National University of Kyiv, National Technical University of Ukraine “Igor Sikorsky Kyiv Polytechnic Institute, etc.)

Scientific and technical developments of the department

The department has a number of scientific and technical developments that can find practical application.

Research Scientists of the Department

Granchak Vasyl Mychaylovych, leading researcher, doctor of sciences.
tel.: +38(044)5256712, fax: +38 (044)5256712 e-mail: granchakvm@ukr.net
Shvalagin Vitaliy Vasylovych, senior researcher, candidate of sciences. 
tel.: + 38(044)5255858, e-mail: shvalagin@inphyschem-nas.kiev.ua
Grodzyuk Galina Yaroslavivna, researcher, candidate of sciences.
tel.: + 38(044)5250270 e-mail: nanosvin@meta.ua
Ovcharov Mykhailo Leonidovych, researcher, candidate of sciences. 
tel.: + 38(044)5250270, e-mail: nanosvin@meta.ua
Kozytskiy Andriy Volodymyrovych researcher, candidate of sciences. 
tel.: + 38(044)5250270, e-mail: kozytskiy@gmail.com

Scientific equipment of the Department

1. Luminescence spectrometer LS 55 (Perkin Elmer)

2. Spectrophotometer Specord 210 (Analytik Jena)

3. Gas Chromatographs CHROM-5 and CHROM-4 (Laboratorní přístroje).

4. Keithley’s Standard Series 2400 Source Measure Unit (Keithley Instruments, Inc.).

List of selected publications

1. Kuchmiy S.Ya. Photocatalytic neutralization of light organic air pollutants using graphite-like carbon nitride (Review) // Theoret. Experim. Chem. – 2021. – 57, № 4 – P. 201-223.

2. Vitaliy Shvalagin, Stepan Kuchmiy, Mykola Skoryk, Marina Bondarenko, Oleg Khyzhun Acid treated crystalline graphitic carbon nitride with improved efficiency in photocatalytic ethanol oxidation under visible light // Materials Science and Engineering: B, Volume 271, 2021, 115304.

3. Vitaliy V. Shvalagin, Ganna V. Korzhak, Stepan Ya. Kuchmiy, Mykola A. Skoryk, Oleksandr V. Selyshchev, Dietrich R.T. Zahn Facile preparation and high photocatalytic activity of crystalline graphitic carbon nitride in hydrogen evolution from electron donor solutions under visible light // Journal of Photochemistry and Photobiology A: Chemistry. – Volume 390, 2020, 112295.

4. Natalya Andryushina, Vitaliy Shvalagin, Ganna Korzhak, Galyna Grodzyuk, Stepan Kuchmiy, Mykola Skoryk Photocatalytic evolution of H2 from aqueous solutions of two-component electron-donor substrates in the presence of g-C3N4 activated by heat treatment in the KCl+LiCl melt // Applied Surface Science 475 (2019) 348–354.

5. Stroyuk O., Kozytskiy A., Kuchmiy S. Photocatalytic formation of composite electrodes for semiconductor-sensitized solar cells // In: Photoelectrochemical solar cells / Ed.by N.D. Sankir and M. Sankir. – Scrivener Publishing, Wiley, USA, 2018. – P. 425-458.

6. Raevskaya A., Panasiuk V., Korzhak G., Stroyuk O., Kuchmiy S., Dzhagan V., Zahn D. Photocatalytic H2 production from aqueous solutions of hydrazine and its derivatives in the presence of nitric-acid-activated graphitic carbon nitride // Catalysis Today. – 2017. – 284. – P. 229-235. 

7. Shvalagin, V.V., Grodzyuk, G.Y., Korzhak, G.V., Andriushyna N. S., Kuchmy S. Ya., Siroshenko Yu. E., Skoryk M. A. Photocatalytic properties of layered K3H3Nb10.8O30 in the hydrogen evolution reaction from aqueous solutions of alcohols // Theoret. Experim. Chem. – 2017. – 53, № 2. – P. 100-105. 

8. Raevskaya A., Rosovik O., Kozytskiy A., Stroyuk O., Dzhagan V., Zahn D.R.T. Non-stoichiometric Cu–In–S@ZnS nanoparticles produced in aqueous solutions as light harvesters for liquid-junction photoelectrochemical solar cells // RSC Adv. – 2016. – 6, N 102. – P. 100145–100157. 

9. Stroyuk O. L., Kuchmiy S. Ya. Semiconductor-based photocatalytic systems for solar-light-driven water splitting and hydrogen evolution: fundamentals, state-of-the-art and perspectives // Photocatalysis: fundamentals, applications and prospects / Ed. by Margaret Howard. – Nova Science Publishers, Inc., New York. – 2015. – Р. 31-84. 

10. Stroyuk O.L., Andryushina N.S., Kuchmiy S.Ya., Pokhodenko V.D. Photochemical processes involving graphene oxide (Review) // Theoret. Experim. Chem. – 2015. – 51, № 1. – P. 1-26. 

11. Rayevska O. E., Stroyuk O. L., Grodzyuk G. Y., Kuchmiy S.Y., Dzhagan V.M., Valakh M.Y. Ultra-small CdS quantum dots capped by amine polyelectrolytes // Handbook of Functional Nanomaterials. V. 1. Synthesis and Modification / Ed. by M. Aliofkhazraei. – New York – USA: Nova Science Publishers, Ltd., 2014. – P. 49–70. 

12. Granchak V.M., Sakhno T.V., Kuchmiy S.Ya. Light-emitting materials – active components of luminescent solar concentrators (Review) // Theoret. Experim. Chem. – 2014. – 50, № 1. – P. 1-20. 

13. Kozytskiy A. V., Stroyuk O. L., Kuchmiy S. Ya. Inorganic photoelectrochemical solar cells based on nanocrystalline ZnO/ZnSe and ZnO/CuSe heterostructures // Catal. Today. – 2014. – 230. – P. 227-233. 

14. M.L. Ovcharov, V.V. Shvalagin, V. M. Granchak Photocatalytic Reduction of Carbon Dioxide by Water Vapor on Mesoporous Titania Modified by Bimetallic Au/Cu Nanostructures // Theoret. Experim. Chem. – 2014. – 50, № 1. – P. 53-58. 

15. Kryukov A.I., Stroyuk O.L., Kuchmiy S.Ya., Pokhodenko V.D. Nanophotocatalysis. – Kiev: Academperiodyka, 2013. – 618 p.

 List of selected patents

1. V.V.Shvalagin, G.Ya.Grodziuk, S.Ya. Kuchmiy Method of producing photocatalyst based on crystalline carbon nitride for oxidation of alcohols. Patent of Ukraine № 143633 dated 10.08.2020.

2. Ya.V. Panasyuk, O.E. Raevskaya, O.L. Stroyuk, S.Ya. Kuchmiy Method of obtaining high-luminescent material based on monolayered carbon nitride. Patent of Ukraine № 110285 dated 10.10.2016.

3. M.Ya. Vortman, G. Ya.Grodziuk, 1. V.V.Shvalagin, V.M. Granchak, S.Ya. Kuchmiy, V.M. Lemeshko, G.V. Dudarenko, T.S.Ivanova, S.O. Trigub, V.V. Shevchenko The use of epoxy photoluminescent composition as a coating agent in the paint industry. Patent of Ukraine № 101360 dated 10.09.2015. 

4. A.V. Kozytsky, O.L. Stroyuk, S.Ya. Kuchmiy Method of photocatalytic production of film material FTO/TiO2/CuS. Patent of Ukraine № 98914 dated 12.05.2015. 

5. M.Ya. Vortman, G. Ya.Grodziuk, 1. V.V.Shvalagin, V.M. Granchak, S.Ya. Kuchmiy, V.M. Lemeshko, G.V. Dudarenko, T.S.Ivanova, S.O. Trigub, V.V. Shevchenko Polymer photoluminescent material. Patent of Ukraine № 95213 dated 10.12.2014. 

6. V.H. Sysiuk, V.M. Granchak Photopolymerizable adhesive for finishing printed products by cold foil stamping. Patent of Ukraine № 99202 dated 25.07.2012.