Kenneth Graham, assistant professor of chemistry at the University of Kentucky, has been selected as a recipient of a CAREER Award from the U.S. Department of Energy. This award supports the development of individual research programs of outstanding scientists early in their careers and stimulates research programs in the disciplines supported by the DOE Office of Science.

The chemistry at organic-inorganic interfaces plays a major role in determining the performance of electronic and optoelectronic devices, and the electronic and optical properties of organic-inorganic composite materials. Understanding, developing and using surface chemistry is thus essential for creating improved and novel materials and devices.

One class of materials that will benefit tremendously from an improved fundamental understanding of the surface chemistry is organometal halide perovskites and metal halide perovskites, (O)MHPs. These perovskites are emerging as inexpensive materials that can be printed from solution to make efficient photovoltaic cells for harvesting solar energy, light emitting diodes for energy efficient solid-state lighting applications, solid-state lasers and transistors.

To realize the potential of (O)MHPs, their surface chemistry and interfacial properties must be better understood and utilized. Thus, the objectives of this research include quantifying ligand binding strengths; determining how the ligands influence photoluminescence properties, energetics and charge transfer processes; determining how ligands influence stability; developing strategies improve stability; and developing mixed surface ligands to systematically manipulate energetics, charge transfer and stability at perovskite-organic interfaces, as well as the performance and stability of perovskite photovoltaics and light emitting diodes.

The $750,000 award, “Surface Ligand Effects on Energetics, Charge Transfer, and Stability at Interfaces Between Metal Halide Perovskites and Organic Semiconductors,” will establish key information regarding the surface chemistry of organometal halide perovskites and metal halide perovskites, (O)MHPs, that can be widely applied in both academics and industry to facilitate the development of this exciting material class.