CAREER: Understand electro-reduction of Fe ions and oxides in aqueous electrolytes

Water-based (aqueous) iron batteries are a promising technology for low-cost, grid-scale stationary energy storage. This technology could store energy for renewable electricity generation such as solar or wind. In addition, electrolytic ironmaking is a promising technology for the ironmaking industry. At the core of these technologies is the reduction of iron ions and oxides to metallic iron using electrical current. This project will generate fundamental knowledge on the mechanism and reactivity of these chemistries. The knowledge will enable the rational design of iron metal batteries, which have the potential to reduce energy storage costs. The new knowledge will also enable the design and development of novel low-temperature electrolytic ironmaking processes, which could strengthen the competitiveness of the nation’s iron and steel industry. Additionally, the project will develop an education program that integrates outreach, research, and teaching which will create systematic opportunities for attracting and retaining engineering students into energy research and industry. The primary goal of this project is to obtain fundamental understanding of the electro-reduction of Fe ions and oxides in acidic aqueous electrolytes, and how the reaction mechanism and reactivity depends on the chemical environment. Experimental (e.g. electrochemical, microscopic and spectroscopic) and modeling methods will be combined to understand the electro-reduction thermodynamics and kinetics of Fe ions, the pathway of hematite electro-reduction, and the correlations of electro-reduction reactivity and the chemical environment. The fundamental knowledge can guide the design of electrolytes to accelerate the development of Fe metal batteries and guide the design of lower emission ironmaking processes. The established models can be generalized to understand the electro-reduction of other transition metal ions. The knowledge on hematite electro-reduction can be extended to the electro-reduction of other Fe oxide ores (magnetite, goethite, siderite) and electro-metallurgy of other transition metal oxides. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.