Nick Serpone | Università degli studi di Pavia (original) (raw)
Papers by Nick Serpone
Journal of Physical Chemistry C, 2007
The photoassisted oxidative transformation of the highly recalcitrant cyanuric acid was examined ... more The photoassisted oxidative transformation of the highly recalcitrant cyanuric acid was examined in the liquidsolid regime at pH 3 and natural pH 7.5 under UV irradiation in oxygen-and ozone-saturated ZnO suspensions using ZnO as a photomediator. Loss of cyanuric acid was assayed by HPLC UV absorption spectroscopy, whereas intermediates and final products were determined by HPLC ion chromatography (IC), by MS techniques using an electrospray ionization mass spectrometer operated in the negative-ion mode, and by FT-IR spectroscopy. Final reaction products were CO 2 gas and NO 3ions. The measure of nitrate in solution quantified the degree of mineralization of the substrate; its concentration in solution was lower than indicated by the loss of cyanuric acid owing to adsorption of the latter to the ZnO surface. Some degree of corrosion of ZnO occurred as evidenced by the quantity of Zn 2+ present in acidic and near-neutral aqueous media before and during the photoassisted process. The possible site(s) and mode(s) of adsorption of cyanuric acid on ZnO have been inferred from theoretical calculations of point charges; the position(s) of attack of the substrate by • OH radicals was inferred from frontier electron density calculations. Mechanistic considerations are based on the possible involvement of Zn 2+ -cyanurate species (chemisorbed cyanuric acid) in the degradation of such a recalcitrant substrate, inasmuch as the use of TiO 2 -photoassisted processes under similar conditions have so far failed to oxidize cyanuric acid.
Journal of Photochemistry, 1981
Coordination Chemistry Reviews, 1985
Coordination Chemistry Reviews, 64 (1985) 225-245 Elsevier SciencePublishers B.V.,Amsterdam-Print... more Coordination Chemistry Reviews, 64 (1985) 225-245 Elsevier SciencePublishers B.V.,Amsterdam-Printedin The Netherlands
The Journal of Physical Chemistry, 1991
Role of OH Radlcals and Trapped Holes In Photocatalysis. A Pulse Radlolysls Study ... Chemistry D... more Role of OH Radlcals and Trapped Holes In Photocatalysis. A Pulse Radlolysls Study ... Chemistry Department, Concordia University, Montrtal. Qutbec, Canada H3G I M8 ... Chemistry Division, Argonne National Laboratory, Argonne, Illinois 60439 (Received: November 27, ...
Organic Process Research & Development, 2008
This article reports for the first time the rapid one-pot solventfree synthesis of 1-butyl-3-meth... more This article reports for the first time the rapid one-pot solventfree synthesis of 1-butyl-3-methylimidazolium tetrafluoroborate ([bmim]BF 4 ), a major ionic liquid, in good yields (87%) after 30 min of microwave irradiation with microwaves at a frequency of 5.8 GHz in a batch-mode reactor. By contrast, the yields of [bmim]BF 4 are about 3-to-4-fold smaller when using 2.45-GHz microwave radiation and oil bath heating: 28% and 21%, respectively, under otherwise identical conditions. This further shows the advantage(s) of the 5.8-GHz microwave radiation and the accompanying apparatus as a novel synthetic tool reported in some detail elsewhere {Org. Process Res. DeW.. 2008, 12, 257-263}. The three synthetic methods (viz., 5.8-GHz and 2.45-GHz microwave heating, and oil bath heating) were examined in reactors used in both the batch and reflux modes. In the latter mode, the yields of [bmim]BF 4 were less than 10% even after a 60-min reaction period. The dependence of the synthesis on the frequency of the microwave radiation is discussed in terms of the chemical yields of the product and the dielectric factors of each substrate in the synthesis mixtures composed of 1-methylimidazole, 1-chlorobutane, and sodium tetrafluoroborate.
New Journal of Chemistry, 2008
... E-mail: nick.serpone@unipv.it; nickser@alcor.concordia.ca. ... Products were separated and pu... more ... E-mail: nick.serpone@unipv.it; nickser@alcor.concordia.ca. ... Products were separated and purified by flash column chromatography over silica gel-300; the eluent was a mixture of dichloromethane and n-hexane (1 : 2 volume ratio). ...
Journal of Photochemistry, 1986
... GRATZEL Institut de Chimie Physique, Ecole Polytechnique Federale de Lausanne, Ecublens, CH-1... more ... GRATZEL Institut de Chimie Physique, Ecole Polytechnique Federale de Lausanne, Ecublens, CH-1015 (Switzerland) EZIO PELIZZETTI istituto di Chimica Analitica, Universitd di Torino, 10126 Torino (Italy) NICK SERPONE Department of ... WF Holman and KJ Macek, Trans. Am. ...
Angewandte Chemie International Edition, 2014
International Journal of Photoenergy, 2001
This article briefly reviews some of our recent work carried out both from an experimental point ... more This article briefly reviews some of our recent work carried out both from an experimental point of view as well as from a theoretical perspective to gain further understanding of the events that take place in Heterogeneous Photocatalysis. Previously, the multitude of reports from our laboratory and from many others looked at the primary photocatalytic events as involving (a) absorption of light, (b) formation of the free (electrons and holes) and/or trapped charge carriers (Ti 3+ and •OH radicals), and (c) reaction of pre-adsorbed acceptor or donor molecules with the relevant trapped carrier. Our recent work notes that this view is reasonable if the only purpose of photocatalysis is elimination of undesirable environmental pollutants. But when we begin to query how to render a process more efficient, we need to address the primary events following photoexcitation of the photocatalyst, which in most instances has been titanium dioxide (in the anatase form). Owing to the nature of light absorption by TiO 2 we resorted to examining other metal oxides, most of which are dielectric insulators with very large bandgap energies, for example zirconia (ZrO 2 ) and scandia (Sc 2 O 3 ). These dielectrics have provided added information on the photophysical events, many of which are masked by the strong light absorption in titania. Despite some of our recent progress, much remains to be done for a fuller understanding of the events that occur at the surface, which we have often considered to be the greatest and most complex defect in metal oxide particulates.
The Journal of Physical Chemistry, 1995
The Journal of Physical Chemistry, 1989
Pulse radiolysis has been used to optically and kinetically characterize the transient free radic... more Pulse radiolysis has been used to optically and kinetically characterize the transient free radicals formed by the reaction of H', N3', or OH' with 2,4,5-trichlorophenoI (TCP-OH). The hydroxy-2,4,5-trichlorocyclohexadienyl radical (H-TCP-OH) formed by H' addition to TCP-OH [ k = (1.1 f 0.2) X lo9 M-' s-' ] has an absorption maximum at 360 nm with 6360 = (4700 & 1000) M-I cm-I. The 2,4,5-trichlorophenoxyl radical (TCP-0') formed by the reaction of N3* with TCP-0-[ k = (4.3 & 0.8) X lo9 M-l s-]] has an absorption maximum at 430 nm with €430 = (3600 f 600) M-l cm-l. The dihydroxy-2,4,5-trichlorocyclohexadienyl radical (HO-TCP-OH) formed by OH' radical addition to TCP-OH [k = (1.2 f 0.1) X 1Olo M-I s-I] has an absorption maximum at 320 nm with €320 = (5300 & 250) M-I cm-I. The principal isomer formed by the reaction of OH' with TCP-OH is the 1,6-dihydroxy-2,4,5-trichlorocyclohexadienyl radical, which has a pK, of 4.8 & 1.0. The solution absorption from each radical decays via second-order kinetics on the millisecond time scale.
Small (Weinheim an der Bergstrasse, Germany), Jan 19, 2015
Ferroelectric materials have been studied increasingly for solar energy conversion technologies d... more Ferroelectric materials have been studied increasingly for solar energy conversion technologies due to the efficient charge separation driven by the polarization induced internal electric field. However, their insufficient conversion efficiency is still a major challenge. Here, a photocathode material of epitaxial double perovskite Bi2 FeCrO6 multiferroic thin film is reported with a suitable conduction band position and small bandgap (1.9-2.1 eV), for visible-light-driven reduction of water to hydrogen. Photoelectrochemical measurements show that the highest photocurrent density up to -1.02 mA cm(-2) at a potential of -0.97 V versus reversible hydrogen electrode is obtained in p-type Bi2 FeCrO6 thin film photocathode grown on SrTiO3 substrate under AM 1.5G simulated sunlight. In addition, a twofold enhancement of photocurrent density is obtained after negatively poling the Bi2 FeCrO6 thin film, as a result of modulation of the band structure by suitable control of the internal elec...
Coordination Chemistry Reviews, 1981
Coordination Chemistry Reviews, 1983
Journal of the Chemical Society, Chemical Communications, 1980
Coordination Chemistry Reviews, 1981
Coordination Chemistry Reviews, 1989
Surfactants in Solution, 1991
LOUPY:MICROWAVE 3E 2VOLS O-BK, 2012
Journal of Physical Chemistry C, 2007
The photoassisted oxidative transformation of the highly recalcitrant cyanuric acid was examined ... more The photoassisted oxidative transformation of the highly recalcitrant cyanuric acid was examined in the liquidsolid regime at pH 3 and natural pH 7.5 under UV irradiation in oxygen-and ozone-saturated ZnO suspensions using ZnO as a photomediator. Loss of cyanuric acid was assayed by HPLC UV absorption spectroscopy, whereas intermediates and final products were determined by HPLC ion chromatography (IC), by MS techniques using an electrospray ionization mass spectrometer operated in the negative-ion mode, and by FT-IR spectroscopy. Final reaction products were CO 2 gas and NO 3ions. The measure of nitrate in solution quantified the degree of mineralization of the substrate; its concentration in solution was lower than indicated by the loss of cyanuric acid owing to adsorption of the latter to the ZnO surface. Some degree of corrosion of ZnO occurred as evidenced by the quantity of Zn 2+ present in acidic and near-neutral aqueous media before and during the photoassisted process. The possible site(s) and mode(s) of adsorption of cyanuric acid on ZnO have been inferred from theoretical calculations of point charges; the position(s) of attack of the substrate by • OH radicals was inferred from frontier electron density calculations. Mechanistic considerations are based on the possible involvement of Zn 2+ -cyanurate species (chemisorbed cyanuric acid) in the degradation of such a recalcitrant substrate, inasmuch as the use of TiO 2 -photoassisted processes under similar conditions have so far failed to oxidize cyanuric acid.
Journal of Photochemistry, 1981
Coordination Chemistry Reviews, 1985
Coordination Chemistry Reviews, 64 (1985) 225-245 Elsevier SciencePublishers B.V.,Amsterdam-Print... more Coordination Chemistry Reviews, 64 (1985) 225-245 Elsevier SciencePublishers B.V.,Amsterdam-Printedin The Netherlands
The Journal of Physical Chemistry, 1991
Role of OH Radlcals and Trapped Holes In Photocatalysis. A Pulse Radlolysls Study ... Chemistry D... more Role of OH Radlcals and Trapped Holes In Photocatalysis. A Pulse Radlolysls Study ... Chemistry Department, Concordia University, Montrtal. Qutbec, Canada H3G I M8 ... Chemistry Division, Argonne National Laboratory, Argonne, Illinois 60439 (Received: November 27, ...
Organic Process Research & Development, 2008
This article reports for the first time the rapid one-pot solventfree synthesis of 1-butyl-3-meth... more This article reports for the first time the rapid one-pot solventfree synthesis of 1-butyl-3-methylimidazolium tetrafluoroborate ([bmim]BF 4 ), a major ionic liquid, in good yields (87%) after 30 min of microwave irradiation with microwaves at a frequency of 5.8 GHz in a batch-mode reactor. By contrast, the yields of [bmim]BF 4 are about 3-to-4-fold smaller when using 2.45-GHz microwave radiation and oil bath heating: 28% and 21%, respectively, under otherwise identical conditions. This further shows the advantage(s) of the 5.8-GHz microwave radiation and the accompanying apparatus as a novel synthetic tool reported in some detail elsewhere {Org. Process Res. DeW.. 2008, 12, 257-263}. The three synthetic methods (viz., 5.8-GHz and 2.45-GHz microwave heating, and oil bath heating) were examined in reactors used in both the batch and reflux modes. In the latter mode, the yields of [bmim]BF 4 were less than 10% even after a 60-min reaction period. The dependence of the synthesis on the frequency of the microwave radiation is discussed in terms of the chemical yields of the product and the dielectric factors of each substrate in the synthesis mixtures composed of 1-methylimidazole, 1-chlorobutane, and sodium tetrafluoroborate.
New Journal of Chemistry, 2008
... E-mail: nick.serpone@unipv.it; nickser@alcor.concordia.ca. ... Products were separated and pu... more ... E-mail: nick.serpone@unipv.it; nickser@alcor.concordia.ca. ... Products were separated and purified by flash column chromatography over silica gel-300; the eluent was a mixture of dichloromethane and n-hexane (1 : 2 volume ratio). ...
Journal of Photochemistry, 1986
... GRATZEL Institut de Chimie Physique, Ecole Polytechnique Federale de Lausanne, Ecublens, CH-1... more ... GRATZEL Institut de Chimie Physique, Ecole Polytechnique Federale de Lausanne, Ecublens, CH-1015 (Switzerland) EZIO PELIZZETTI istituto di Chimica Analitica, Universitd di Torino, 10126 Torino (Italy) NICK SERPONE Department of ... WF Holman and KJ Macek, Trans. Am. ...
Angewandte Chemie International Edition, 2014
International Journal of Photoenergy, 2001
This article briefly reviews some of our recent work carried out both from an experimental point ... more This article briefly reviews some of our recent work carried out both from an experimental point of view as well as from a theoretical perspective to gain further understanding of the events that take place in Heterogeneous Photocatalysis. Previously, the multitude of reports from our laboratory and from many others looked at the primary photocatalytic events as involving (a) absorption of light, (b) formation of the free (electrons and holes) and/or trapped charge carriers (Ti 3+ and •OH radicals), and (c) reaction of pre-adsorbed acceptor or donor molecules with the relevant trapped carrier. Our recent work notes that this view is reasonable if the only purpose of photocatalysis is elimination of undesirable environmental pollutants. But when we begin to query how to render a process more efficient, we need to address the primary events following photoexcitation of the photocatalyst, which in most instances has been titanium dioxide (in the anatase form). Owing to the nature of light absorption by TiO 2 we resorted to examining other metal oxides, most of which are dielectric insulators with very large bandgap energies, for example zirconia (ZrO 2 ) and scandia (Sc 2 O 3 ). These dielectrics have provided added information on the photophysical events, many of which are masked by the strong light absorption in titania. Despite some of our recent progress, much remains to be done for a fuller understanding of the events that occur at the surface, which we have often considered to be the greatest and most complex defect in metal oxide particulates.
The Journal of Physical Chemistry, 1995
The Journal of Physical Chemistry, 1989
Pulse radiolysis has been used to optically and kinetically characterize the transient free radic... more Pulse radiolysis has been used to optically and kinetically characterize the transient free radicals formed by the reaction of H', N3', or OH' with 2,4,5-trichlorophenoI (TCP-OH). The hydroxy-2,4,5-trichlorocyclohexadienyl radical (H-TCP-OH) formed by H' addition to TCP-OH [ k = (1.1 f 0.2) X lo9 M-' s-' ] has an absorption maximum at 360 nm with 6360 = (4700 & 1000) M-I cm-I. The 2,4,5-trichlorophenoxyl radical (TCP-0') formed by the reaction of N3* with TCP-0-[ k = (4.3 & 0.8) X lo9 M-l s-]] has an absorption maximum at 430 nm with €430 = (3600 f 600) M-l cm-l. The dihydroxy-2,4,5-trichlorocyclohexadienyl radical (HO-TCP-OH) formed by OH' radical addition to TCP-OH [k = (1.2 f 0.1) X 1Olo M-I s-I] has an absorption maximum at 320 nm with €320 = (5300 & 250) M-I cm-I. The principal isomer formed by the reaction of OH' with TCP-OH is the 1,6-dihydroxy-2,4,5-trichlorocyclohexadienyl radical, which has a pK, of 4.8 & 1.0. The solution absorption from each radical decays via second-order kinetics on the millisecond time scale.
Small (Weinheim an der Bergstrasse, Germany), Jan 19, 2015
Ferroelectric materials have been studied increasingly for solar energy conversion technologies d... more Ferroelectric materials have been studied increasingly for solar energy conversion technologies due to the efficient charge separation driven by the polarization induced internal electric field. However, their insufficient conversion efficiency is still a major challenge. Here, a photocathode material of epitaxial double perovskite Bi2 FeCrO6 multiferroic thin film is reported with a suitable conduction band position and small bandgap (1.9-2.1 eV), for visible-light-driven reduction of water to hydrogen. Photoelectrochemical measurements show that the highest photocurrent density up to -1.02 mA cm(-2) at a potential of -0.97 V versus reversible hydrogen electrode is obtained in p-type Bi2 FeCrO6 thin film photocathode grown on SrTiO3 substrate under AM 1.5G simulated sunlight. In addition, a twofold enhancement of photocurrent density is obtained after negatively poling the Bi2 FeCrO6 thin film, as a result of modulation of the band structure by suitable control of the internal elec...
Coordination Chemistry Reviews, 1981
Coordination Chemistry Reviews, 1983
Journal of the Chemical Society, Chemical Communications, 1980
Coordination Chemistry Reviews, 1981
Coordination Chemistry Reviews, 1989
Surfactants in Solution, 1991
LOUPY:MICROWAVE 3E 2VOLS O-BK, 2012