TY - JOUR
T1 - Electroactivity of nanoporous platinum depending on the porosity and potential for various electrode reactions
AU - Cho, Yun Bin
AU - Kim, Ji Eon
AU - Lee, Chongmok
AU - Lee, Youngmi
N1 - Funding Information:
This work was financially supported by the National Research Foundation of Korea (NRF) funded by the Ministry of Science, ICT and Future Planning ( 2014R1A2A2A05003769 for YL) and ( 2014R1A2A2A01005479 for CL).
Publisher Copyright:
© 2016 Elsevier B.V. All rights reserved.
PY - 2016/5/1
Y1 - 2016/5/1
N2 - Electroactivity of nanoporous Pt (npPt) depending on the pore characteristics was studied for various electrode reactions having a range of electrode reaction kinetics: ferrocene oxidation, l-ascorbic acid (AA) oxidation, oxygen reduction reaction (ORR), H2O2 reduction, and glucose oxidation. npPts with two different degrees of the porosities (npPt-1 and npPt-2) were electrodeposited on recessed Pt microdisk electrodes (100-μm diameter), employing deposition solutions in which the composition ratios of Pt precursor, Triton X-100, and lead acetate were varied. npPt-1 has smaller microscale pores than npPt-2. The electroactivities of npPts were analyzed using amperometric sensitivities at mass-transfer-controlled and kinetic-controlled potential regions. Both npPt-1 and npPt-2 increased the sensitivities for all the reactions but reversible ferrocene oxidation remarkably compared to bare Pt. In the kinetic-controlled region, npPt-1 showed more greatly enhanced sensitivity compared to npPt-2 due to the smaller pores exerting more efficient confinement of a reactant near the Pt surface. In mass-transfer controlled region, npPt-2 was beneficial for relatively fast reactions (AA oxidation, ORR); while npPt-1 was advantageous for slower reactions (H2O2 reduction, glucose oxidation). This suggests that the particle-to-particle distance of the npPt affects the electroactivity and an optimum degree of the porosity is different depending on the reaction kinetics.
AB - Electroactivity of nanoporous Pt (npPt) depending on the pore characteristics was studied for various electrode reactions having a range of electrode reaction kinetics: ferrocene oxidation, l-ascorbic acid (AA) oxidation, oxygen reduction reaction (ORR), H2O2 reduction, and glucose oxidation. npPts with two different degrees of the porosities (npPt-1 and npPt-2) were electrodeposited on recessed Pt microdisk electrodes (100-μm diameter), employing deposition solutions in which the composition ratios of Pt precursor, Triton X-100, and lead acetate were varied. npPt-1 has smaller microscale pores than npPt-2. The electroactivities of npPts were analyzed using amperometric sensitivities at mass-transfer-controlled and kinetic-controlled potential regions. Both npPt-1 and npPt-2 increased the sensitivities for all the reactions but reversible ferrocene oxidation remarkably compared to bare Pt. In the kinetic-controlled region, npPt-1 showed more greatly enhanced sensitivity compared to npPt-2 due to the smaller pores exerting more efficient confinement of a reactant near the Pt surface. In mass-transfer controlled region, npPt-2 was beneficial for relatively fast reactions (AA oxidation, ORR); while npPt-1 was advantageous for slower reactions (H2O2 reduction, glucose oxidation). This suggests that the particle-to-particle distance of the npPt affects the electroactivity and an optimum degree of the porosity is different depending on the reaction kinetics.
KW - Electrocatalysis
KW - Electrode reaction kinetics
KW - Nanoporous structure
KW - Platinum
KW - Porosity
UR - http://www.scopus.com/inward/record.url?scp=84960385919&partnerID=8YFLogxK
U2 - 10.1016/j.jelechem.2016.03.002
DO - 10.1016/j.jelechem.2016.03.002
M3 - Article
AN - SCOPUS:84960385919
SN - 1572-6657
VL - 768
SP - 121
EP - 128
JO - Journal of Electroanalytical Chemistry
JF - Journal of Electroanalytical Chemistry
ER -