Non-Technical Abstract: Developing efficient and green energy conversion technologies is of strategic importance for the United States energy and environmental sustainability. Compared with conventional fossil fuel combustion devices, proton exchange membrane fuel cells (PEMFCs) hold great potentials for both transportation and stationary grid applications since they are cleaner, more affordable, and more reliable; they run with renewable hydrogen fuel; and they demonstrate high efficiency with minimized carbon emission. This project aims to develop an emerging class of nanostructured materials with one-dimensional architecture and core/shell structure which can maximize the benefit of PEMFCs. The rational design and precise preparation of such nanomaterials can significantly advance the understanding of both materials design and synthesis for efficient and cost-effective PEMFCs and many other applications, including batteries, electrolyzers, and electrochemical sensors. The outcome of this project can accelerate the large-scale application of PEMFCs, potentially transform the United States energy portfolio, and establish an eco-benign energy society. An education plan is designed to be integrated with research activities to promote teaching, training and learning at several levels, covering K-12, undergraduate and graduate students. Parts of the activities include educational outreach involving underrepresented minorities. The project can attract, build and retain a high-quality next-generation workforce in catalysis, energy technology and other science, technology, engineering, and math (STEM) fields.
Proton exchange membrane fuel cells (PEMFCs), based on renewable hydrogen sources, play a critical role in establishing a sustainable and clean hydrogen energy economy to reduce our society's dependency on conventional fossil fuels and the related combustion technologies. Advanced PEMFCs suitable for large-scale transportation and stationary grid powers demand a nanostructured material that can be used to accelerate the cathodic oxygen reduction reaction (ORR) with a high activity over a sufficiently long period of time and with minimized platinum group metal usage. The objective of this project is to design and synthesize one-dimensional core-shell nanocrystals with non-precious-metal cores, by precisely controlling their core-shell material compositions and physical parameters (e.g. lengths of one-dimensional nanorods, core-shell interfaces, and shell profiles), to fundamentally understand the correlation of atomic level nanocrystal architecture to the favorable electrocatalytic properties. The Principle Investigator leverages the expertise in nanomaterials synthesis, structural characterization, electrochemistry and theoretical calculation, to primarily focus on four tasks: (1) Rationally designing and synthesizing cobalt phosphide-platinum core-shell nanorods with controlled lengths and shell profiles; (2) Tuning the core-shell interface and structural arrangements; (3) Optimizing the efficiency of nanocrystals by using transition metal doped cobalt phosphide nanorod cores; and (4) Understanding the design rules for optimized ORR conversion through a combination of electrochemical, spectroscopic, and computational approaches. The generated knowledge accelerates the development of new forms of nanomaterials by exploiting the mechanism controls of synthesis at the atomic level and uncovers how to correlate and control their functional activity and structural stability.
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.
