Materials Discovery Across Technological Readiness Levels

NREL can work across at each technology readiness level—basic science, applied research, and device development—demonstrating competence in a broad range of materials discovery problems.

Basic Science

An image of a triangular diagram with tantalum-cobalt-tin at the top vertex, tantalum at the lower left vertex, and cobalt at the lower right vertex. Documented materials, such as cobalt tin, are marked along the edges. Stable, unstable, and undetermined materials are marked within a cluster within the central portion of the triangle.

The Materials Discovery process at the most fundamental levels starts from the growth of materials that have never been synthesized before. This includes determining the chemical composition and crystallographic structure of the new materials, and it is akin to discovering a new planet in astronomy or documenting a new species in biology.

Examples of Work

These publications provide examples of our prior work in the basic science area.

Novel Phase Diagram Behavior and Materials Design in Heterostructural Semiconductor Alloys, Science Advances (2017)

Synthesis of a Mixed-Valent Tin Nitride and Considerations of Its Possible Crystal Structures,  J. Chem. Phys. (2016)

Theoretical Prediction and Experimental Realization of New Stable Inorganic Materials Using Inverse Design ApproachJ. Am. Chem. Soc. (2013)

Applied Research

The more practical aspect of Materials Discovery focuses on materials properties (e.g., optical absorption, electrical conductivity, work function) and the combination of them (e.g., transparent conductors, solar absorbers), rather than on the materials themselves (composition and structure discussed above). Such applied research is the first step toward the material's practical use in devices.

An image of a map of copper nitride growth showing target-to-substrate distance along vertical axis and temperature along horizontal axis. Points are plotted in this space indicating degree of orientation. High-degree points are clustered along the left edge and low-degree points along the right edge, with intermediate points mostly within the left-hand region.

Examples of Work

One aspect of applied research in materials discovery is demonstrating a useful combination of properties in a material that has been previously reported, yet not characterized for these properties. These publications provide examples of our capabilities in this area.

Synthesis and Characterization of (Sn,Zn)O AlloysChemistry of Materials (2016)

Self-Regulated Growth and Tunable Properties of CuSbS2 Solar Absorbers, Solar Energy Materials and Solar Cells  (2015)

Thin Film Synthesis and Properties of Copper Nitride, a Metastable SemiconductorMater. Horiz. (2014)

An image of a combinatorial map with oxygen partial pressure on y axis and temperature on x axis.  Various rectangular samples are shown within this area, with colors indicating different conductivity values, from lowest in the upper left to highest in the lower left.

Another aspect of applied research in materials discovery includes explaining the origins of enhanced/suppressed properties in prototypical functional materials. This allows the distilling of design principles on which the discovery of new materials can be based. These publications provide examples of our research within this area.

Effects of Hydrogen on Acceptor Activation in Ternary Nitride Semiconductors, Advanced Electronic Materials (2017)

Defect Tolerant Semiconductors for Solar Energy Conversion, J. Phys. Chem. Lett.  (2014)

Non-Equilibrium Origin of High Electrical Conductivity in Gallium Zinc Oxide Thin Films, Appl. Phys. Lett. (2013)

Device Development

An image of a block diagram of solar cell with seven 'exploded' layers highlighted and labeled with composition and thickness. From top to bottom, the layers are aluminum, aluminum zinc oxide, zinc oxide, cadmium sulfide, copper antimony sulfide, molybdenum, and soda-lime glass.

The ultimate goal of materials discovery is the practical application of new materials in useful devices such as solar cells or transistors. And there are a myriad of interesting challenges that arise from materials interactions, associated with integrating multiple materials with optimal properties into a single device.

Examples of Work

These publications provide examples of our research capabilities in the device development area.

Trade-Offs in Thin Film Solar Cells with Layered Chalcostibite Photovoltaic AbsorbersAdvanced Energy Materials (2017)

Combinatorial In Situ Photoelectron Spectroscopy Investigation of Sb2Se3/ZnS Heterointerfaces, Adv. Mater. Interfaces (2016)

Combinatorial Reactive Sputtering of In2S3 as an Alternative Contact Layer for Thin Film Solar CellsACS Applied Materials & Interfaces (2016)