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Published on: January 8, 2016
Synergistic effects in multicomponent electrocatalysts: the Pb-Ir-O system
Conor Mullens1, Michael Pikulski, Sabri Agachan
1Department of Chemistry, University of Texas at San Antonio, San Antonio, Texas 78249-0698, USA.
Journal of the American Chemical Society
|October 30, 2003
Summary
This study developed a new method for creating iridium-based catalytic surfaces using lead and iridium compounds. The resulting lead-iridium oxide (PbIrOx) films show enhanced catalytic activity for carbohydrate electrooxidation.
Area of Science:
- Electrochemistry
- Materials Science
- Catalysis
Background:
- Developing efficient iridium-based catalysts is crucial for various electrochemical applications.
- Understanding ionic interactions in solution is key to designing novel synthetic routes for metal oxides.
Purpose of the Study:
- To investigate ionic interactions in Na(3)IrCl(6) + Pb(NO(3))(2) solutions.
- To develop a facilitated electrosynthesis of iridium-based catalytic surfaces.
- To evaluate the catalytic activity of the synthesized mixed metal oxide films.
Main Methods:
- Spectroscopic studies to identify ion pair charge-transfer complexes.
- Electrochemical studies to analyze overpotential for nucleation and growth.
- Characterization of PbIrOx film stoichiometry and surface properties.
Main Results:
- Formation of ion pair complexes: [IrCl(6)(3-)]-Pb(II) and [Ir(H(2)O)Cl(5)(2-)]-Pb(II).
- Synergistic lowering of overpotential for PbIrOx film growth on glassy carbon electrodes.
- PbIrOx films exhibited a 1:1 Ir:Pb stoichiometry, similar to the pyrochlore phase.
- PbIrOx films showed enhanced catalytic activity for carbohydrate electrooxidation compared to IrOx.
Conclusions:
- A novel synergistic electroplating method was established for synthesizing homogeneous and reactive PbIrOx films.
- The enhanced catalytic activity is attributed to synergistic effects between Pb(II) and Ir(IV) sites.
- This work presents a new synthetic route for mixed metal oxide films with potential applications in catalysis.
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