Electroactivity of nanoporous platinum depending on the porosity and potential for various electrode reactions
- 주제(키워드) Electrocatalysis , Electrode reaction kinetics , Nanoporous structure , Platinum , Porosity
- 등재 SCIE, SCOPUS
- 발행기관 Elsevier
- 발행년도 2016
- 총서유형 Journal
- URI http://www.dcollection.net/handler/ewha/000000125524
- 본문언어 영어
- Published As http://dx.doi.org/10.1016/j.jelechem.2016.03.002
- 저작권 이화여자대학교 논문은 저작권에 의해 보호받습니다.
초록/요약
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. © 2016 Elsevier B.V. All rights reserved.
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