The Role of Iron in Alkaline Electrochemical C-C Bond Oxidation
Abstract
In this STIR project, the role of iron incorporation into nominally PtRuNi nanoparticle catalysts will be studied. The goal of this project is to understand how iron incorporation influences the reaction mechanism of ethanol electrooxidation in alkaline conditions. To our knowledge, iron incorporation into PtRuNi catalysts remains uninvestigated but is likely to occur in any Ni-based catalyst through doping of iron impurities from non-purified alkaline electrolyte. The long-term goal of this research is to determine the mechanism(s) of catalytic activity and reaction specificity recently identified in PtRuNi-based electrocatalysts. These catalysts have been shown to be among the most active for ethanol electrooxidation and facilitate carbon-carbon (C-C) bond oxidation to carbon dioxide. In alkaline electrolyte, surface Ni species will be in a nickel hydroxide phase, regardless of the initial synthesized metallic phase. Further, it was recently discovered in the water electrolysis field that iron impurities from alkaline electrolyte will dope into nickel hydroxide in as few as ten electrochemical cycles or by simply soaking in the electrolyte lover several hours. As this iron doping mechanism is a fundamental mechanism that occurs in any unpurified alkaline electrolyte, it is likely that the high-activity PtRuNi electrocatalysts underwent iron doping during electrochemical testing, which was performed in unpurified electrolyte. This project aims to study this currently un-discovered role of iron in PtRuNi catalysts by synthesizing trimetallic PtRuNi nanoparticles and intentionally doping with iron in alkaline electrolyte. In comparison, quaternary PtRuNiFe nanoparticles will also be studied. Electrochemical testing will include in situ spectroscopy and mass spectrometry studies to confirm ethanol degradation products and delineate the reaction pathway. Ultimately, this research will enable the accelerated development of PtRuNi-based and other Ni-based catalysts through a clear understanding of the role of iron, where the role of iron doping and incorporation into the catalyst structure remains largely uninvestigated, apart from the water electrolysis community.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Feb 14, 2019
- Source ID
- W911NF1810317
Entities
People
- Lauren F Greenlee
Organizations
- Army Contracting Command
- United States Army
- University of Arkansas