The surface characteristics of different carbon materials: activated carbon, carbon felt, glassy carbon and a porous carbon monolith were investigated. The specific surface area was examined by the BET method with N2 adsorption, the amount and the type of surface oxygen groups by Boehm titration as well as by temperature-programmed desorption (TPD). By comparing the results obtained using BET analysis with those of TPD and the Boehm method, it was found that the number of surface groups was not proportional to the specific surface area. The total amount of oxygen groups, obtained by TPD, is higher than the amount obtained by Boehm's method for porous samples. The inconsistencies between these results originate from the fact that the Boehm method is limited to the determination of acidic and basic groups, whereas TPD provides information on the total number of all surface oxygen groups. In addition, the presence of porosity could reduce the solvent-accessible surface in the Boehm method.... The TPD profiles of CO evolution showed the presence of a low temperature maximum, below 650 K, which originates from CO2 reduction on the carbon material surface.
Ispitivane su površinske osobine različitih karbonskih materijala: aktivnog uglja, karbonskog filca, staklastog ugljenika i poroznog karbon monolita. Specifična površina uzoraka ispitivana je BET metodom, a količina i tip površinskih grupa Bemovim titracijama i temperaturski programiranom desorpcijom (TPD). Poredeći rezultate dobijene BET metodom sa rezultatima TPD-a i Bemove titracije, zaključeno je da broj površinskih grupa nije proporcionalan specifičnoj površini uzoraka. Ukupan broj kiseoničnih grupa kod poroznih uzoraka, dobijen na osnovu TPD-a, je veći nego u slučaju Bemovih titracija. Razlog neslaganja rezultata ovih dveju metoda potiče iz činjenice da je Bemov metod ograničen na određivanje samo kiselih i baznih grupa, dok TPD daje informaciju o ukupnom broju svih kiseoničnih grupa. Takođe, kod Bemovog metoda, postojanje poroznosti može smanjiti rastvoru dostupnu površinu. TPD spektri izdvajanja SO pokazali su nisko-temperaturski maksimum, ispod 650 K, koji potiče od redukcije ...SO2 na površini karbonskog materijala.
Keywords:
carbon materials / surface oxygen groups / temperature programmed desorption
Source:
Journal of the Serbian Chemical Society, 2011, 76, 5, 757-768
Publisher:
Serbian Chemical Society, Belgrade
Funding / projects:
Ministry of Science and Technological Development of the Republic Serbia [151005B, 142002]
TY - JOUR
AU - Kalijadis, Ana
AU - Vukčević, Marija
AU - Jovanović, Zoran M.
AU - Laušević, Zoran
AU - Laušević, Mila
PY - 2011
UR - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/1802
AB - The surface characteristics of different carbon materials: activated carbon, carbon felt, glassy carbon and a porous carbon monolith were investigated. The specific surface area was examined by the BET method with N2 adsorption, the amount and the type of surface oxygen groups by Boehm titration as well as by temperature-programmed desorption (TPD). By comparing the results obtained using BET analysis with those of TPD and the Boehm method, it was found that the number of surface groups was not proportional to the specific surface area. The total amount of oxygen groups, obtained by TPD, is higher than the amount obtained by Boehm's method for porous samples. The inconsistencies between these results originate from the fact that the Boehm method is limited to the determination of acidic and basic groups, whereas TPD provides information on the total number of all surface oxygen groups. In addition, the presence of porosity could reduce the solvent-accessible surface in the Boehm method. The TPD profiles of CO evolution showed the presence of a low temperature maximum, below 650 K, which originates from CO2 reduction on the carbon material surface.
AB - Ispitivane su površinske osobine različitih karbonskih materijala: aktivnog uglja, karbonskog filca, staklastog ugljenika i poroznog karbon monolita. Specifična površina uzoraka ispitivana je BET metodom, a količina i tip površinskih grupa Bemovim titracijama i temperaturski programiranom desorpcijom (TPD). Poredeći rezultate dobijene BET metodom sa rezultatima TPD-a i Bemove titracije, zaključeno je da broj površinskih grupa nije proporcionalan specifičnoj površini uzoraka. Ukupan broj kiseoničnih grupa kod poroznih uzoraka, dobijen na osnovu TPD-a, je veći nego u slučaju Bemovih titracija. Razlog neslaganja rezultata ovih dveju metoda potiče iz činjenice da je Bemov metod ograničen na određivanje samo kiselih i baznih grupa, dok TPD daje informaciju o ukupnom broju svih kiseoničnih grupa. Takođe, kod Bemovog metoda, postojanje poroznosti može smanjiti rastvoru dostupnu površinu. TPD spektri izdvajanja SO pokazali su nisko-temperaturski maksimum, ispod 650 K, koji potiče od redukcije SO2 na površini karbonskog materijala.
PB - Serbian Chemical Society, Belgrade
T2 - Journal of the Serbian Chemical Society
T1 - Characterisation of surface oxygen groups on different carbon materials by the Boehm method and temperature-programmed desorption
T1 - Karakterizacija površinskih kiseoničnih grupa različitih karbonskih materijala Bemovom (Boehm) metodom i temperaturski programiranom desorpcijom
EP - 768
IS - 5
SP - 757
VL - 76
UR - https://hdl.handle.net/21.15107/rcub_technorep_1802
ER -
@article{
author = "Kalijadis, Ana and Vukčević, Marija and Jovanović, Zoran M. and Laušević, Zoran and Laušević, Mila",
year = "2011",
abstract = "The surface characteristics of different carbon materials: activated carbon, carbon felt, glassy carbon and a porous carbon monolith were investigated. The specific surface area was examined by the BET method with N2 adsorption, the amount and the type of surface oxygen groups by Boehm titration as well as by temperature-programmed desorption (TPD). By comparing the results obtained using BET analysis with those of TPD and the Boehm method, it was found that the number of surface groups was not proportional to the specific surface area. The total amount of oxygen groups, obtained by TPD, is higher than the amount obtained by Boehm's method for porous samples. The inconsistencies between these results originate from the fact that the Boehm method is limited to the determination of acidic and basic groups, whereas TPD provides information on the total number of all surface oxygen groups. In addition, the presence of porosity could reduce the solvent-accessible surface in the Boehm method. The TPD profiles of CO evolution showed the presence of a low temperature maximum, below 650 K, which originates from CO2 reduction on the carbon material surface., Ispitivane su površinske osobine različitih karbonskih materijala: aktivnog uglja, karbonskog filca, staklastog ugljenika i poroznog karbon monolita. Specifična površina uzoraka ispitivana je BET metodom, a količina i tip površinskih grupa Bemovim titracijama i temperaturski programiranom desorpcijom (TPD). Poredeći rezultate dobijene BET metodom sa rezultatima TPD-a i Bemove titracije, zaključeno je da broj površinskih grupa nije proporcionalan specifičnoj površini uzoraka. Ukupan broj kiseoničnih grupa kod poroznih uzoraka, dobijen na osnovu TPD-a, je veći nego u slučaju Bemovih titracija. Razlog neslaganja rezultata ovih dveju metoda potiče iz činjenice da je Bemov metod ograničen na određivanje samo kiselih i baznih grupa, dok TPD daje informaciju o ukupnom broju svih kiseoničnih grupa. Takođe, kod Bemovog metoda, postojanje poroznosti može smanjiti rastvoru dostupnu površinu. TPD spektri izdvajanja SO pokazali su nisko-temperaturski maksimum, ispod 650 K, koji potiče od redukcije SO2 na površini karbonskog materijala.",
publisher = "Serbian Chemical Society, Belgrade",
journal = "Journal of the Serbian Chemical Society",
title = "Characterisation of surface oxygen groups on different carbon materials by the Boehm method and temperature-programmed desorption, Karakterizacija površinskih kiseoničnih grupa različitih karbonskih materijala Bemovom (Boehm) metodom i temperaturski programiranom desorpcijom",
pages = "768-757",
number = "5",
volume = "76",
url = "https://hdl.handle.net/21.15107/rcub_technorep_1802"
}
Kalijadis, A., Vukčević, M., Jovanović, Z. M., Laušević, Z.,& Laušević, M.. (2011). Characterisation of surface oxygen groups on different carbon materials by the Boehm method and temperature-programmed desorption. in Journal of the Serbian Chemical Society
Serbian Chemical Society, Belgrade., 76(5), 757-768.
https://hdl.handle.net/21.15107/rcub_technorep_1802
Kalijadis A, Vukčević M, Jovanović ZM, Laušević Z, Laušević M. Characterisation of surface oxygen groups on different carbon materials by the Boehm method and temperature-programmed desorption. in Journal of the Serbian Chemical Society. 2011;76(5):757-768.
https://hdl.handle.net/21.15107/rcub_technorep_1802 .
Kalijadis, Ana, Vukčević, Marija, Jovanović, Zoran M., Laušević, Zoran, Laušević, Mila, "Characterisation of surface oxygen groups on different carbon materials by the Boehm method and temperature-programmed desorption" in Journal of the Serbian Chemical Society, 76, no. 5 (2011):757-768,
https://hdl.handle.net/21.15107/rcub_technorep_1802 .
