TY  - JOUR
AU  - Pozio, Alfonso
AU  - Jovanović, Zoran M.
AU  - Tosti, Silvano
PY  - 2019
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/8593
AB  - Hydrogen retention in Pd–Ag (silver 21 wt. %) thin foil has been tested by means of temperature-programmed desorption (TPD) in the temperature range 25–200 °C and compared to the resistivity measurements for the purpose of explaining the characteristic S-shaped resistivity curve and its minimum observed in the same temperature range. The TPD results indicated that the highest uptake of hydrogen was between 65 °C and 105 °C, with a maximum at ~85 °C. Furthermore, in all examined cases, the hydrogen desorption peak was between 140 °C and 180 °C. The resistivity measurements in argon, hydrogen, and vacuum allowed us to examine the influence of hydrogen on the resistivity of a Pd–Ag alloy. The results showed evidence of two kinds of hydrides: (1) a weak absorption at low temperature (T < 70 °C) with the hydrogen present mainly in tetrahedral sites, and (2) a strong absorption up to 150 °C with the hydrogen present mainly in octahedral sites. The behaviour of the electrical resistivity and the minimum between 90 °C and 110 °C can be explained by the two kinds of hydrogen uploaded into the metal lattice.
T2  - Materials
T1  - Hydrogen Absorption in Pd–Ag Systems: A TPD and Electrical Resistivity Study
VL  - 12
IS  - 19
SP  - 3160
DO  - 10.3390/ma12193160
ER  - 

@article{
author = "Pozio, Alfonso and Jovanović, Zoran M. and Tosti, Silvano",
year = "2019",
abstract = "Hydrogen retention in Pd–Ag (silver 21 wt. %) thin foil has been tested by means of temperature-programmed desorption (TPD) in the temperature range 25–200 °C and compared to the resistivity measurements for the purpose of explaining the characteristic S-shaped resistivity curve and its minimum observed in the same temperature range. The TPD results indicated that the highest uptake of hydrogen was between 65 °C and 105 °C, with a maximum at ~85 °C. Furthermore, in all examined cases, the hydrogen desorption peak was between 140 °C and 180 °C. The resistivity measurements in argon, hydrogen, and vacuum allowed us to examine the influence of hydrogen on the resistivity of a Pd–Ag alloy. The results showed evidence of two kinds of hydrides: (1) a weak absorption at low temperature (T < 70 °C) with the hydrogen present mainly in tetrahedral sites, and (2) a strong absorption up to 150 °C with the hydrogen present mainly in octahedral sites. The behaviour of the electrical resistivity and the minimum between 90 °C and 110 °C can be explained by the two kinds of hydrogen uploaded into the metal lattice.",
journal = "Materials",
title = "Hydrogen Absorption in Pd–Ag Systems: A TPD and Electrical Resistivity Study",
volume = "12",
number = "19",
pages = "3160",
doi = "10.3390/ma12193160"
}

Pozio, A., Jovanović, Z. M.,& Tosti, S.. (2019). Hydrogen Absorption in Pd–Ag Systems: A TPD and Electrical Resistivity Study. in Materials, 12(19), 3160.
https://doi.org/10.3390/ma12193160

Pozio A, Jovanović ZM, Tosti S. Hydrogen Absorption in Pd–Ag Systems: A TPD and Electrical Resistivity Study. in Materials. 2019;12(19):3160.
doi:10.3390/ma12193160 .

Pozio, Alfonso, Jovanović, Zoran M., Tosti, Silvano, "Hydrogen Absorption in Pd–Ag Systems: A TPD and Electrical Resistivity Study" in Materials, 12, no. 19 (2019):3160,
https://doi.org/10.3390/ma12193160 . .

TY  - JOUR
AU  - Pozio, Alfonso
AU  - Jovanović, Zoran M.
AU  - Lo Presti, R.
AU  - De Francesco, M.
AU  - Tosti, Silvano
PY  - 2012
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/4877
AB  - A Pd-Ag (silver 21 wt.%) thin sheet has been tested in order to measure its electrical resistivity by means of electrochemical impedance spectroscopy under different hydrogenation conditions in the temperature range 25-350 degrees C. The metal sheet has been assembled with the electrical contacts in a gas tight module where pure hydrogen has been fed at a pressure of 100 and 200 kPa. The electrical resistivity vs. both the temperature and hydrogen pressure presents a characteristic S-shape curve with a minimum and a maximum of the resistivity. This behaviour permitted to recognize three stages: (1) introduction of H into Pd-Ag lattice up to a well-defined HIM ratio increases the resistivity; (2) further uptake of hydrogen with a decrease of resistivity until a higher HIM ratio; (3) above this higher HIM ratio the resistivity increases sharply. The behaviour of the electrical resistivity is discussed in details by considering the hydrogen uploading into the metal lattice, its effect on the conduction electrons and the scattering of the hydrogen atoms into the metal lattice. Copyright (C) 2012, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.
T2  - International Journal of Hydrogen Energy
T1  - Pd-Ag hydrogen content and electrical resistivity: Temperature and pressure effect
VL  - 37
IS  - 9
SP  - 7925
EP  - 7933
DO  - 10.1016/j.ijhydene.2012.01.108
ER  - 

@article{
author = "Pozio, Alfonso and Jovanović, Zoran M. and Lo Presti, R. and De Francesco, M. and Tosti, Silvano",
year = "2012",
abstract = "A Pd-Ag (silver 21 wt.%) thin sheet has been tested in order to measure its electrical resistivity by means of electrochemical impedance spectroscopy under different hydrogenation conditions in the temperature range 25-350 degrees C. The metal sheet has been assembled with the electrical contacts in a gas tight module where pure hydrogen has been fed at a pressure of 100 and 200 kPa. The electrical resistivity vs. both the temperature and hydrogen pressure presents a characteristic S-shape curve with a minimum and a maximum of the resistivity. This behaviour permitted to recognize three stages: (1) introduction of H into Pd-Ag lattice up to a well-defined HIM ratio increases the resistivity; (2) further uptake of hydrogen with a decrease of resistivity until a higher HIM ratio; (3) above this higher HIM ratio the resistivity increases sharply. The behaviour of the electrical resistivity is discussed in details by considering the hydrogen uploading into the metal lattice, its effect on the conduction electrons and the scattering of the hydrogen atoms into the metal lattice. Copyright (C) 2012, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.",
journal = "International Journal of Hydrogen Energy",
title = "Pd-Ag hydrogen content and electrical resistivity: Temperature and pressure effect",
volume = "37",
number = "9",
pages = "7925-7933",
doi = "10.1016/j.ijhydene.2012.01.108"
}

Pozio, A., Jovanović, Z. M., Lo Presti, R., De Francesco, M.,& Tosti, S.. (2012). Pd-Ag hydrogen content and electrical resistivity: Temperature and pressure effect. in International Journal of Hydrogen Energy, 37(9), 7925-7933.
https://doi.org/10.1016/j.ijhydene.2012.01.108

Pozio A, Jovanović ZM, Lo Presti R, De Francesco M, Tosti S. Pd-Ag hydrogen content and electrical resistivity: Temperature and pressure effect. in International Journal of Hydrogen Energy. 2012;37(9):7925-7933.
doi:10.1016/j.ijhydene.2012.01.108 .

Pozio, Alfonso, Jovanović, Zoran M., Lo Presti, R., De Francesco, M., Tosti, Silvano, "Pd-Ag hydrogen content and electrical resistivity: Temperature and pressure effect" in International Journal of Hydrogen Energy, 37, no. 9 (2012):7925-7933,
https://doi.org/10.1016/j.ijhydene.2012.01.108 . .

TY  - JOUR
AU  - Pozio, Alfonso
AU  - De Francesco, M.
AU  - Jovanović, Zoran M.
AU  - Tosti, Silvano
PY  - 2011
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/4320
AB  - This paper describes experimental work involving the direct-current electrolysis of potassium hydroxide solutions at medium temperatures (up to 80 degrees C) and atmospheric pressure. An electrolytic cell with a palladium silver alloy cathode as a source of ultrapure hydrogen was designed and tested. This cathode consists of a dense Pd-Ag tube capable to selectively separate hydrogen from other gases. Thin wall thickness (50 mu m) of the permeator tube permitted to attain high hydrogen permeation fluxes and high hydrogen yields. Starting from results, a prototype electrolyzer is designed. Copyright (C) 2011, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.
T2  - International Journal of Hydrogen Energy
T1  - Pd-Ag hydrogen diffusion cathode for alkaline water electrolysers
VL  - 36
IS  - 9
SP  - 5211
EP  - 5217
DO  - 10.1016/j.ijhydene.2011.01.168
ER  - 

@article{
author = "Pozio, Alfonso and De Francesco, M. and Jovanović, Zoran M. and Tosti, Silvano",
year = "2011",
abstract = "This paper describes experimental work involving the direct-current electrolysis of potassium hydroxide solutions at medium temperatures (up to 80 degrees C) and atmospheric pressure. An electrolytic cell with a palladium silver alloy cathode as a source of ultrapure hydrogen was designed and tested. This cathode consists of a dense Pd-Ag tube capable to selectively separate hydrogen from other gases. Thin wall thickness (50 mu m) of the permeator tube permitted to attain high hydrogen permeation fluxes and high hydrogen yields. Starting from results, a prototype electrolyzer is designed. Copyright (C) 2011, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.",
journal = "International Journal of Hydrogen Energy",
title = "Pd-Ag hydrogen diffusion cathode for alkaline water electrolysers",
volume = "36",
number = "9",
pages = "5211-5217",
doi = "10.1016/j.ijhydene.2011.01.168"
}

Pozio, A., De Francesco, M., Jovanović, Z. M.,& Tosti, S.. (2011). Pd-Ag hydrogen diffusion cathode for alkaline water electrolysers. in International Journal of Hydrogen Energy, 36(9), 5211-5217.
https://doi.org/10.1016/j.ijhydene.2011.01.168

Pozio A, De Francesco M, Jovanović ZM, Tosti S. Pd-Ag hydrogen diffusion cathode for alkaline water electrolysers. in International Journal of Hydrogen Energy. 2011;36(9):5211-5217.
doi:10.1016/j.ijhydene.2011.01.168 .

Pozio, Alfonso, De Francesco, M., Jovanović, Zoran M., Tosti, Silvano, "Pd-Ag hydrogen diffusion cathode for alkaline water electrolysers" in International Journal of Hydrogen Energy, 36, no. 9 (2011):5211-5217,
https://doi.org/10.1016/j.ijhydene.2011.01.168 . .

TY  - JOUR
AU  - Jovanović, Zoran M.
AU  - De Francesco, M.
AU  - Tosti, Silvano
AU  - Pozio, Alfonso
PY  - 2011
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/4400
AB  - The palladium (79%) silver (21%) alloy has been characterized in respect to the permeation efficiency of electrolytically produced hydrogen. The effect of discontinuous electrolysis on permeation performance has been discussed as well as methods for Pd-Ag electrode reactivation. The structural changes of PdAg alloy, induced by electrolytic hydrogen adsorption, have been analyzed in details and were correlated with the H/Pd atomic ratio. By performing the electrolysis for well defined time, we managed to control the H/Pd ratio over the whole range of alpha- and beta-phase stability, as defined by phase diagram. The beta-phase formation was accompanied with surface corrugation of Pd-Ag alloy. As we determined, surface corrugation caused the occurrence of ghost peak in XRD spectra of PdAg alloy that coincides with the alpha-phase peak, thus influencing its resolution. Also, the criteria that should be taken into account when analyzing XRD data of H PdAg alloy were established. Copyright (C) 2011, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.
T2  - International Journal of Hydrogen Energy
T1  - Structural modification of PdAg alloy induced by electrolytic hydrogen absorption
VL  - 36
IS  - 13
SP  - 7728
EP  - 7736
DO  - 10.1016/j.ijhydene.2011.03.112
ER  - 

@article{
author = "Jovanović, Zoran M. and De Francesco, M. and Tosti, Silvano and Pozio, Alfonso",
year = "2011",
abstract = "The palladium (79%) silver (21%) alloy has been characterized in respect to the permeation efficiency of electrolytically produced hydrogen. The effect of discontinuous electrolysis on permeation performance has been discussed as well as methods for Pd-Ag electrode reactivation. The structural changes of PdAg alloy, induced by electrolytic hydrogen adsorption, have been analyzed in details and were correlated with the H/Pd atomic ratio. By performing the electrolysis for well defined time, we managed to control the H/Pd ratio over the whole range of alpha- and beta-phase stability, as defined by phase diagram. The beta-phase formation was accompanied with surface corrugation of Pd-Ag alloy. As we determined, surface corrugation caused the occurrence of ghost peak in XRD spectra of PdAg alloy that coincides with the alpha-phase peak, thus influencing its resolution. Also, the criteria that should be taken into account when analyzing XRD data of H PdAg alloy were established. Copyright (C) 2011, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.",
journal = "International Journal of Hydrogen Energy",
title = "Structural modification of PdAg alloy induced by electrolytic hydrogen absorption",
volume = "36",
number = "13",
pages = "7728-7736",
doi = "10.1016/j.ijhydene.2011.03.112"
}

Jovanović, Z. M., De Francesco, M., Tosti, S.,& Pozio, A.. (2011). Structural modification of PdAg alloy induced by electrolytic hydrogen absorption. in International Journal of Hydrogen Energy, 36(13), 7728-7736.
https://doi.org/10.1016/j.ijhydene.2011.03.112

Jovanović ZM, De Francesco M, Tosti S, Pozio A. Structural modification of PdAg alloy induced by electrolytic hydrogen absorption. in International Journal of Hydrogen Energy. 2011;36(13):7728-7736.
doi:10.1016/j.ijhydene.2011.03.112 .

Jovanović, Zoran M., De Francesco, M., Tosti, Silvano, Pozio, Alfonso, "Structural modification of PdAg alloy induced by electrolytic hydrogen absorption" in International Journal of Hydrogen Energy, 36, no. 13 (2011):7728-7736,
https://doi.org/10.1016/j.ijhydene.2011.03.112 . .

TY  - JOUR
AU  - Jovanović, Zoran M.
AU  - De Francesco, M.
AU  - Tosti, Silvano
AU  - Pozio, Alfonso
PY  - 2011
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/4573
AB  - The influence of surface oxidation and hydrogen upload into the Pd(0.79)Ag(0.21) membrane on hydrogen permeation was examined by measuring the permeation of: 1) gas-phase H(2) sent from the electrode back-side and 2) electrolytic H2 produced on electrolyte side. It was verified that hydrogen upload into PdAg lattice has positive effect i.e. increases hydrogen permeation, while surface oxides formed during and after electrolysis cycles are the main factors acting on decrease of hydrogen permeation. Particularly, silver oxides are identified as permeation-blocking species. Consequently, several treatments were proposed aiming to reduce electrode deactivation; beside wet chemistry treatments applicable after electrolysis, the in situ electrode reactivation by ultrasonic pulses was presented. Copyright (C) 2011, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.
T2  - International Journal of Hydrogen Energy
T1  - Influence of surface activation on the hydrogen permeation properties of PdAg cathode membrane
VL  - 36
IS  - 23
SP  - 15364
EP  - 15371
DO  - 10.1016/j.ijhydene.2011.08.098
ER  - 

@article{
author = "Jovanović, Zoran M. and De Francesco, M. and Tosti, Silvano and Pozio, Alfonso",
year = "2011",
abstract = "The influence of surface oxidation and hydrogen upload into the Pd(0.79)Ag(0.21) membrane on hydrogen permeation was examined by measuring the permeation of: 1) gas-phase H(2) sent from the electrode back-side and 2) electrolytic H2 produced on electrolyte side. It was verified that hydrogen upload into PdAg lattice has positive effect i.e. increases hydrogen permeation, while surface oxides formed during and after electrolysis cycles are the main factors acting on decrease of hydrogen permeation. Particularly, silver oxides are identified as permeation-blocking species. Consequently, several treatments were proposed aiming to reduce electrode deactivation; beside wet chemistry treatments applicable after electrolysis, the in situ electrode reactivation by ultrasonic pulses was presented. Copyright (C) 2011, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.",
journal = "International Journal of Hydrogen Energy",
title = "Influence of surface activation on the hydrogen permeation properties of PdAg cathode membrane",
volume = "36",
number = "23",
pages = "15364-15371",
doi = "10.1016/j.ijhydene.2011.08.098"
}

Jovanović, Z. M., De Francesco, M., Tosti, S.,& Pozio, A.. (2011). Influence of surface activation on the hydrogen permeation properties of PdAg cathode membrane. in International Journal of Hydrogen Energy, 36(23), 15364-15371.
https://doi.org/10.1016/j.ijhydene.2011.08.098

Jovanović ZM, De Francesco M, Tosti S, Pozio A. Influence of surface activation on the hydrogen permeation properties of PdAg cathode membrane. in International Journal of Hydrogen Energy. 2011;36(23):15364-15371.
doi:10.1016/j.ijhydene.2011.08.098 .

Jovanović, Zoran M., De Francesco, M., Tosti, Silvano, Pozio, Alfonso, "Influence of surface activation on the hydrogen permeation properties of PdAg cathode membrane" in International Journal of Hydrogen Energy, 36, no. 23 (2011):15364-15371,
https://doi.org/10.1016/j.ijhydene.2011.08.098 . .