TY - JOUR
T1 - Key factors improving oxygen reduction reaction activity in cobalt nanoparticles modified carbon nanotubes
AU - Gabe, Atsushi
AU - García-Aguilar, Jaime
AU - Berenguer-Murcia, Ángel
AU - Morallón, Emilia
AU - Cazorla-Amorós, Diego
N1 - Funding Information:
The authors would like to thank GV and FEDER (PROMETEOII/2014/010), projects CTQ2015-66080-R (MINECO/FEDER), MAT2016-76595-R (MINECO/FEDER), BES-2013-063678 and HEIWA NAKAJIMA FOUNDATION for the financial support.
PY - 2017
Y1 - 2017
N2 - Multiwall carbon nanotubes (CNTs) decorated with cobalt oxide (CoOx) nanoparticles (NPs) are prepared in various synthesis conditions to investigate their capability as oxygen reduction reaction (ORR) catalysts for fuel cells in alkaline media. The synthesis conditions include the use of protecting, reducing or complexing agents and heat treatment. Higher ORR activity is possible for smaller size of Co NPs catalysts due to the enlarged interfaces between Co species and CNTs. The addition of polyvinylpyrrolidone (PVP) as protecting agent and NaBH4 during the preparation procedure is necessary for obtaining the highest activity since it favors the formation of lower oxidation states for Co species and the incorporation of N groups which improve ORR activity. CNTs loaded with only 1 wt.% of Co NPs prepared by a facile method using PVP, NaBH4 and subsequent heat treatment at 500 °C under N2 atmosphere, demonstrates both similar catalytic activity and stability than Pt/Vulcan (20 wt.% Pt on Vulcan). The synergic chemical coupling effects between CNTs and CoOx NPs and the presence of carbon material with pyridinic N and quaternary N groups formed from the protecting agent decomposition, seem to be the main factors responsible for the remarkable electrocatalytic activity.
AB - Multiwall carbon nanotubes (CNTs) decorated with cobalt oxide (CoOx) nanoparticles (NPs) are prepared in various synthesis conditions to investigate their capability as oxygen reduction reaction (ORR) catalysts for fuel cells in alkaline media. The synthesis conditions include the use of protecting, reducing or complexing agents and heat treatment. Higher ORR activity is possible for smaller size of Co NPs catalysts due to the enlarged interfaces between Co species and CNTs. The addition of polyvinylpyrrolidone (PVP) as protecting agent and NaBH4 during the preparation procedure is necessary for obtaining the highest activity since it favors the formation of lower oxidation states for Co species and the incorporation of N groups which improve ORR activity. CNTs loaded with only 1 wt.% of Co NPs prepared by a facile method using PVP, NaBH4 and subsequent heat treatment at 500 °C under N2 atmosphere, demonstrates both similar catalytic activity and stability than Pt/Vulcan (20 wt.% Pt on Vulcan). The synergic chemical coupling effects between CNTs and CoOx NPs and the presence of carbon material with pyridinic N and quaternary N groups formed from the protecting agent decomposition, seem to be the main factors responsible for the remarkable electrocatalytic activity.
KW - C-N-Co interaction
KW - Carbon nanotubes
KW - CoOx nanoparticles
KW - Electrocatalyst
KW - Oxygen reduction reaction
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U2 - 10.1016/j.apcatb.2017.05.096
DO - 10.1016/j.apcatb.2017.05.096
M3 - Article
AN - SCOPUS:85020296070
VL - 217
SP - 303
EP - 312
JO - Applied Catalysis B: Environmental
JF - Applied Catalysis B: Environmental
SN - 0926-3373
ER -