Murray State University
Fundamental Studies of Electron Transfer Active Iridium Oxide Nanoparticles in Solutions and on Conducting Surfaces: STUDY 1 (McIntyre): The Effects of Dissolved Carbon Dioxide on the Optical and Electronic Properties of Solutions of Diffusing Iridium Oxide Nanoparticles
Institution
Murray State University
Faculty Advisor/ Mentor
Lloyd P. Horne
Abstract
One promising paradigm in alternative energy research is the photocatalytic conversion of sunlight, via water oxidation, into electrical energy. The overall efficiency of this water-splitting process is hindered by slow electrode kinetics, which result in large overpotentials. To mitigate this problem, research efforts are focused on developing catalysts for driving these electrochemical reactions closer to their respective thermodynamic potentials (i.e., at lower overpotentials). With respect to water oxidation, some of the lowest known overpotentials have been achieved using very small (~2 nm diameter) iridium oxide (IrOx) nanoparticles dispersed in solutions (i.e., freely diffusing) and supported as films immobilized onto electrode surfaces. We have recently discovered that both optical and electronic properties of these nanoparticles are affected by the presence of dissolved gas, such as carbon dioxide. In this study, we report a systematic investigation into these phenomena, as they relate to solar energy conversion.
Fundamental Studies of Electron Transfer Active Iridium Oxide Nanoparticles in Solutions and on Conducting Surfaces: STUDY 1 (McIntyre): The Effects of Dissolved Carbon Dioxide on the Optical and Electronic Properties of Solutions of Diffusing Iridium Oxide Nanoparticles
One promising paradigm in alternative energy research is the photocatalytic conversion of sunlight, via water oxidation, into electrical energy. The overall efficiency of this water-splitting process is hindered by slow electrode kinetics, which result in large overpotentials. To mitigate this problem, research efforts are focused on developing catalysts for driving these electrochemical reactions closer to their respective thermodynamic potentials (i.e., at lower overpotentials). With respect to water oxidation, some of the lowest known overpotentials have been achieved using very small (~2 nm diameter) iridium oxide (IrOx) nanoparticles dispersed in solutions (i.e., freely diffusing) and supported as films immobilized onto electrode surfaces. We have recently discovered that both optical and electronic properties of these nanoparticles are affected by the presence of dissolved gas, such as carbon dioxide. In this study, we report a systematic investigation into these phenomena, as they relate to solar energy conversion.