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Papers by Alexander Vorontsov
Physical Chemistry Chemical Physics, 2018
Graphene quantum dots (GQDs) are important for a variety of applications and designs, and the sha... more Graphene quantum dots (GQDs) are important for a variety of applications and designs, and the shapes of GQDs rely on the energy of their boundaries.
Journal of Chemical Technology & Biotechnology, 2020
International Journal of Quantum Chemistry, 2018
Catalysis Science & Technology, 2018
The synthesized Mg-doped TiO2 nanoparticles (NPs) are superior photocatalysts for CO2 reduction. ... more The synthesized Mg-doped TiO2 nanoparticles (NPs) are superior photocatalysts for CO2 reduction. Most energetically profitable doping is obtained for sites by the use of quantum chemical computations.
Russian Journal of Physical Chemistry A, 2015
Energy and Environment Series, 2016
This chapter considers aspects of gas-phase photocatalysis related to indoor or close space air p... more This chapter considers aspects of gas-phase photocatalysis related to indoor or close space air purification. The formation of diverse by-products during photocatalytic oxidation of air pollutants is very important. However, advanced photocatalysts and low concentrations are leading to clean oxidation with inorganic compounds as the only products. The influence of temperature, air relative humidity, pollutants concentration, and irradiance on the oxidation processes is considered in detail. Microbiological airborne objects and even pollen can be inactivated and mineralized with the help of TiO2-based photocatalysts. Research and commercial prototype air purification reactors are considered in this chapter. Finally, combined processes utilizing additional catalysts and oxidants are demonstrated to be of great promise for practical air purification. While much intensive research has been carried out in the field during the last 20 years, there are still questions and underdeveloped aspects in order for photocatalysis to become competitive widespread air purification technology.
Applied Catalysis A: General, 2016
ABSTRACT The paper reviews recent progress in investigating the combination of two advanced oxida... more ABSTRACT The paper reviews recent progress in investigating the combination of two advanced oxidation techniques, atmospheric pressure non-thermal plasma and photocatalytic oxidation (PCO), for purification of air from CO and organic compounds. Non-thermal plasma (NTP) is created in electric discharges, typically dielectric barrier discharge and corona discharge. Oxidation of air pollutants in these discharges is efficient but a lot of byproducts are generated including nitrogen oxides, ozone and partial oxidation products. Photocatalytic oxidation generated much lower quantities of products but is less efficient especially for compounds with high volatility. There are several types of configurations for combining the two techniques in-plasma photocatalysis, post-plasma photocatalysis, irradiation of photocatalyst with discharge light. It is demonstrated that the combination of the two AOTs leads to higher rate of oxidation and generation of lower concentrations of undesirable byproducts. Synergism of NTP and PCO is not due to light generated in discharge since it is too weak but can be due to the ozone and increased adsorption of intermediates on photocatalyst. The combination is promising for air purification applications but further research is needed for elucidating kinetics and mechanism of action and choosing the best photocatalyst and system geometries.
Applied Catalysis a General, 2009
High Energy Chemistry, 2015
Journal of Catalysis, 2015
The heterogenous reaction of acetone, ethanol, and diethyl ether vapors with air proceeding at ro... more The heterogenous reaction of acetone, ethanol, and diethyl ether vapors with air proceeding at room temperature over honeycomb supported TiO2 under the action of mild UV light results in the complete oxidation of these compounds to carbon dioxide. Intermediate gaseous products of diethyl ether oxidation are acetaldehyde and ethyl acetate. Acetaldehyde is an intermediate in ethanol oxidation. Efficient quantum yields of complete oxidation based on electron transferred and the light incident on the photocatalyst are ∼9%.
Nanostructure Science and Technology, 2010
ABSTRACT Organic sulfur compounds play significant roles in the life of modern humankind. There a... more ABSTRACT Organic sulfur compounds play significant roles in the life of modern humankind. There are many instances of the need to destroy or convert sulfur compounds into useful products. Photocatalytic reactions are capable of removing and transforming these compounds. High reactivity of sulfur compounds allows utilization of a variety of photocatalysts – heterogeneous like TiO2 or other species, homogeneous, heterogeneous, or heterogenized. The transformations are mediated by electron transfer with generation of sulfur radical cations, energy transfer, or hydrogen atom transfer. Further reactions majorly comprise S-oxidation, α-C–H deprotonation, C–S bond cleavage, and polymerization. Reactions with photogenerated OH˙ radicals are also possible.
Catalysis in Industry, 2010
Kinetics and Catalysis, 2010
ABSTRACT The results of many-year studies of the relationship between the physical properties and... more ABSTRACT The results of many-year studies of the relationship between the physical properties and photocatalytic activity of TiO2 and Pt/TiO2 in photocatalytic purification and disinfection of air and water and water photodecomposition with oxygen evolution are presented. Recommendations are given as to finding the optimal method for platinum supporting on TiO2 to achieve the highest possible catalytic activity. Multisite kinetic models of the gas-phase oxidation of simple organic substances are considered. Methods for regenerating the photocatalyst after its deactivation in the oxidation of sulfur-containing organic substances are suggested. New data are discussed on the acceleration of air purification by the combination of photocatalytic oxidation with atmospheric electric discharges, the addition of gaseous hydrogen peroxide, and oxidation on photocatalysts existing in the aerosol state. As compared to pure TiO2, platinated titanium dioxide has a higher capability for disinfection and complete mineralization of microorganisms. Two promising methods for production of hydrogen from water using solar light are presented.
Reaction Kinetics and Catalysis Letters
A Cu(OH)2/α-Fe2O3 photocatalyst is shown to be active in the gas phase oxidation of ethanol under... more A Cu(OH)2/α-Fe2O3 photocatalyst is shown to be active in the gas phase oxidation of ethanol under visible light. The calculated initial quantum efficiency of the ethanol photooxidation is 0.1-1%. However, ethanol is oxidized only into acetic acid, which deactivates the catalyst.
Water Science & Technology, 2007
Topics in Catalysis, 2005
Page 1. Photocatalytic destruction of a thiosulfonate Alexander V. Vorontsova,*, Claude Charvyb, ... more Page 1. Photocatalytic destruction of a thiosulfonate Alexander V. Vorontsova,*, Claude Charvyb, and Claude Lionb aBoreskov Institute of Catalysis, Novosibirsk 630090, Russia bInstitut de Topologie et de dynamique des syste ...
The Journal of Physical Chemistry B, 2005
Physical Chemistry Chemical Physics, 2018
Graphene quantum dots (GQDs) are important for a variety of applications and designs, and the sha... more Graphene quantum dots (GQDs) are important for a variety of applications and designs, and the shapes of GQDs rely on the energy of their boundaries.
Journal of Chemical Technology & Biotechnology, 2020
International Journal of Quantum Chemistry, 2018
Catalysis Science & Technology, 2018
The synthesized Mg-doped TiO2 nanoparticles (NPs) are superior photocatalysts for CO2 reduction. ... more The synthesized Mg-doped TiO2 nanoparticles (NPs) are superior photocatalysts for CO2 reduction. Most energetically profitable doping is obtained for sites by the use of quantum chemical computations.
Russian Journal of Physical Chemistry A, 2015
Energy and Environment Series, 2016
This chapter considers aspects of gas-phase photocatalysis related to indoor or close space air p... more This chapter considers aspects of gas-phase photocatalysis related to indoor or close space air purification. The formation of diverse by-products during photocatalytic oxidation of air pollutants is very important. However, advanced photocatalysts and low concentrations are leading to clean oxidation with inorganic compounds as the only products. The influence of temperature, air relative humidity, pollutants concentration, and irradiance on the oxidation processes is considered in detail. Microbiological airborne objects and even pollen can be inactivated and mineralized with the help of TiO2-based photocatalysts. Research and commercial prototype air purification reactors are considered in this chapter. Finally, combined processes utilizing additional catalysts and oxidants are demonstrated to be of great promise for practical air purification. While much intensive research has been carried out in the field during the last 20 years, there are still questions and underdeveloped aspects in order for photocatalysis to become competitive widespread air purification technology.
Applied Catalysis A: General, 2016
ABSTRACT The paper reviews recent progress in investigating the combination of two advanced oxida... more ABSTRACT The paper reviews recent progress in investigating the combination of two advanced oxidation techniques, atmospheric pressure non-thermal plasma and photocatalytic oxidation (PCO), for purification of air from CO and organic compounds. Non-thermal plasma (NTP) is created in electric discharges, typically dielectric barrier discharge and corona discharge. Oxidation of air pollutants in these discharges is efficient but a lot of byproducts are generated including nitrogen oxides, ozone and partial oxidation products. Photocatalytic oxidation generated much lower quantities of products but is less efficient especially for compounds with high volatility. There are several types of configurations for combining the two techniques in-plasma photocatalysis, post-plasma photocatalysis, irradiation of photocatalyst with discharge light. It is demonstrated that the combination of the two AOTs leads to higher rate of oxidation and generation of lower concentrations of undesirable byproducts. Synergism of NTP and PCO is not due to light generated in discharge since it is too weak but can be due to the ozone and increased adsorption of intermediates on photocatalyst. The combination is promising for air purification applications but further research is needed for elucidating kinetics and mechanism of action and choosing the best photocatalyst and system geometries.
Applied Catalysis a General, 2009
High Energy Chemistry, 2015
Journal of Catalysis, 2015
The heterogenous reaction of acetone, ethanol, and diethyl ether vapors with air proceeding at ro... more The heterogenous reaction of acetone, ethanol, and diethyl ether vapors with air proceeding at room temperature over honeycomb supported TiO2 under the action of mild UV light results in the complete oxidation of these compounds to carbon dioxide. Intermediate gaseous products of diethyl ether oxidation are acetaldehyde and ethyl acetate. Acetaldehyde is an intermediate in ethanol oxidation. Efficient quantum yields of complete oxidation based on electron transferred and the light incident on the photocatalyst are ∼9%.
Nanostructure Science and Technology, 2010
ABSTRACT Organic sulfur compounds play significant roles in the life of modern humankind. There a... more ABSTRACT Organic sulfur compounds play significant roles in the life of modern humankind. There are many instances of the need to destroy or convert sulfur compounds into useful products. Photocatalytic reactions are capable of removing and transforming these compounds. High reactivity of sulfur compounds allows utilization of a variety of photocatalysts – heterogeneous like TiO2 or other species, homogeneous, heterogeneous, or heterogenized. The transformations are mediated by electron transfer with generation of sulfur radical cations, energy transfer, or hydrogen atom transfer. Further reactions majorly comprise S-oxidation, α-C–H deprotonation, C–S bond cleavage, and polymerization. Reactions with photogenerated OH˙ radicals are also possible.
Catalysis in Industry, 2010
Kinetics and Catalysis, 2010
ABSTRACT The results of many-year studies of the relationship between the physical properties and... more ABSTRACT The results of many-year studies of the relationship between the physical properties and photocatalytic activity of TiO2 and Pt/TiO2 in photocatalytic purification and disinfection of air and water and water photodecomposition with oxygen evolution are presented. Recommendations are given as to finding the optimal method for platinum supporting on TiO2 to achieve the highest possible catalytic activity. Multisite kinetic models of the gas-phase oxidation of simple organic substances are considered. Methods for regenerating the photocatalyst after its deactivation in the oxidation of sulfur-containing organic substances are suggested. New data are discussed on the acceleration of air purification by the combination of photocatalytic oxidation with atmospheric electric discharges, the addition of gaseous hydrogen peroxide, and oxidation on photocatalysts existing in the aerosol state. As compared to pure TiO2, platinated titanium dioxide has a higher capability for disinfection and complete mineralization of microorganisms. Two promising methods for production of hydrogen from water using solar light are presented.
Reaction Kinetics and Catalysis Letters
A Cu(OH)2/α-Fe2O3 photocatalyst is shown to be active in the gas phase oxidation of ethanol under... more A Cu(OH)2/α-Fe2O3 photocatalyst is shown to be active in the gas phase oxidation of ethanol under visible light. The calculated initial quantum efficiency of the ethanol photooxidation is 0.1-1%. However, ethanol is oxidized only into acetic acid, which deactivates the catalyst.
Water Science & Technology, 2007
Topics in Catalysis, 2005
Page 1. Photocatalytic destruction of a thiosulfonate Alexander V. Vorontsova,*, Claude Charvyb, ... more Page 1. Photocatalytic destruction of a thiosulfonate Alexander V. Vorontsova,*, Claude Charvyb, and Claude Lionb aBoreskov Institute of Catalysis, Novosibirsk 630090, Russia bInstitut de Topologie et de dynamique des syste ...
The Journal of Physical Chemistry B, 2005