Multi-walled carbon nanotubes (MWCNTs) were used as a support for Pt nanoparticles prepared by the microwave-assisted polyol method. The MWCNTs were pretreated by chemical oxidation (o-MWCNTs) followed by modification by ethylenediamine (eda-MWCNTs). Characterization of both oxidized and eda-modified materials by UV-spectroscopy, cyclic voltammetry and electrochemical impedance spectroscopy revealed that the modification by eda leads to (i) agglomeration of the MWCNTs, (ii) a decrease in the capacitance of the material and (iii) reduced rate of electron transfer between the MWCNTs and solution species. However, the Pt loading of Pt/o-MWCNTs was only 2 mass% while the loading of Pt/eda-MWCNTs was 20 mass%. Much higher efficiency of Pt deposition on eda-MWCNTs than on o-MWCNTs was ascribed to the shift in pH(pzc) value of the MWCNT surface from 2.43 to 5.91 upon modification by eda. Transmission electron microscopy revealed that the mean diameter of the Pt particles in Pt/eda-MWCNTs is 2....5 +/- 0.5 nm and that their distribution on the support is homogenous with no evidence of pronounced particle agglomeration. Cyclic voltammetry of a Pt/eda-MWCNT thin film indicated a clean Pt surface with well-resolved peaks characteristic of polycrystalline Pt. Its electrocatalytic activity for oxygen reduction was examined and the results corresponded to the commercial Pt nanocatalyst. This study shows that modification of o-MWCNTs by eda helps to achieve homogenous distribution of small Pt nanoparticles and does not impede its electrocatalytic activity.
Keywords:
Nanostructures / Electrochemical properties / DTA / TEM
Source:
Materials Chemistry and Physics, 2011, 130, 1-2, 657-664
U.S. Department of Energy, Office of Basic Energy Sciences, Division of Materials Sciences and EngineeringUnited States Department of Energy (DOE) [DE-AC02-05CH11231]
TY - JOUR
AU - Vuković, Goran D.
AU - Obradović, Maja
AU - Marinković, Aleksandar
AU - Rogan, Jelena
AU - Uskoković, Petar
AU - Radmilović, Velimir R.
AU - Gojković, Snežana
PY - 2011
UR - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/1868
AB - Multi-walled carbon nanotubes (MWCNTs) were used as a support for Pt nanoparticles prepared by the microwave-assisted polyol method. The MWCNTs were pretreated by chemical oxidation (o-MWCNTs) followed by modification by ethylenediamine (eda-MWCNTs). Characterization of both oxidized and eda-modified materials by UV-spectroscopy, cyclic voltammetry and electrochemical impedance spectroscopy revealed that the modification by eda leads to (i) agglomeration of the MWCNTs, (ii) a decrease in the capacitance of the material and (iii) reduced rate of electron transfer between the MWCNTs and solution species. However, the Pt loading of Pt/o-MWCNTs was only 2 mass% while the loading of Pt/eda-MWCNTs was 20 mass%. Much higher efficiency of Pt deposition on eda-MWCNTs than on o-MWCNTs was ascribed to the shift in pH(pzc) value of the MWCNT surface from 2.43 to 5.91 upon modification by eda. Transmission electron microscopy revealed that the mean diameter of the Pt particles in Pt/eda-MWCNTs is 2.5 +/- 0.5 nm and that their distribution on the support is homogenous with no evidence of pronounced particle agglomeration. Cyclic voltammetry of a Pt/eda-MWCNT thin film indicated a clean Pt surface with well-resolved peaks characteristic of polycrystalline Pt. Its electrocatalytic activity for oxygen reduction was examined and the results corresponded to the commercial Pt nanocatalyst. This study shows that modification of o-MWCNTs by eda helps to achieve homogenous distribution of small Pt nanoparticles and does not impede its electrocatalytic activity.
PB - Elsevier Science Sa, Lausanne
T2 - Materials Chemistry and Physics
T1 - Ethylenediamine-modified multiwall carbon nanotubes as a Pt catalyst support
EP - 664
IS - 1-2
SP - 657
VL - 130
DO - 10.1016/j.matchemphys.2011.07.046
ER -
@article{
author = "Vuković, Goran D. and Obradović, Maja and Marinković, Aleksandar and Rogan, Jelena and Uskoković, Petar and Radmilović, Velimir R. and Gojković, Snežana",
year = "2011",
abstract = "Multi-walled carbon nanotubes (MWCNTs) were used as a support for Pt nanoparticles prepared by the microwave-assisted polyol method. The MWCNTs were pretreated by chemical oxidation (o-MWCNTs) followed by modification by ethylenediamine (eda-MWCNTs). Characterization of both oxidized and eda-modified materials by UV-spectroscopy, cyclic voltammetry and electrochemical impedance spectroscopy revealed that the modification by eda leads to (i) agglomeration of the MWCNTs, (ii) a decrease in the capacitance of the material and (iii) reduced rate of electron transfer between the MWCNTs and solution species. However, the Pt loading of Pt/o-MWCNTs was only 2 mass% while the loading of Pt/eda-MWCNTs was 20 mass%. Much higher efficiency of Pt deposition on eda-MWCNTs than on o-MWCNTs was ascribed to the shift in pH(pzc) value of the MWCNT surface from 2.43 to 5.91 upon modification by eda. Transmission electron microscopy revealed that the mean diameter of the Pt particles in Pt/eda-MWCNTs is 2.5 +/- 0.5 nm and that their distribution on the support is homogenous with no evidence of pronounced particle agglomeration. Cyclic voltammetry of a Pt/eda-MWCNT thin film indicated a clean Pt surface with well-resolved peaks characteristic of polycrystalline Pt. Its electrocatalytic activity for oxygen reduction was examined and the results corresponded to the commercial Pt nanocatalyst. This study shows that modification of o-MWCNTs by eda helps to achieve homogenous distribution of small Pt nanoparticles and does not impede its electrocatalytic activity.",
publisher = "Elsevier Science Sa, Lausanne",
journal = "Materials Chemistry and Physics",
title = "Ethylenediamine-modified multiwall carbon nanotubes as a Pt catalyst support",
pages = "664-657",
number = "1-2",
volume = "130",
doi = "10.1016/j.matchemphys.2011.07.046"
}
Vuković, G. D., Obradović, M., Marinković, A., Rogan, J., Uskoković, P., Radmilović, V. R.,& Gojković, S.. (2011). Ethylenediamine-modified multiwall carbon nanotubes as a Pt catalyst support. in Materials Chemistry and Physics
Elsevier Science Sa, Lausanne., 130(1-2), 657-664.
https://doi.org/10.1016/j.matchemphys.2011.07.046
Vuković GD, Obradović M, Marinković A, Rogan J, Uskoković P, Radmilović VR, Gojković S. Ethylenediamine-modified multiwall carbon nanotubes as a Pt catalyst support. in Materials Chemistry and Physics. 2011;130(1-2):657-664.
doi:10.1016/j.matchemphys.2011.07.046 .
Vuković, Goran D., Obradović, Maja, Marinković, Aleksandar, Rogan, Jelena, Uskoković, Petar, Radmilović, Velimir R., Gojković, Snežana, "Ethylenediamine-modified multiwall carbon nanotubes as a Pt catalyst support" in Materials Chemistry and Physics, 130, no. 1-2 (2011):657-664,
https://doi.org/10.1016/j.matchemphys.2011.07.046 . .
