Name: Shuting Feng
Department: Chemical Engineering
School: Massachusetts Institute of Technology
Project: Computation-assisted Design of Stable and Ion-conducting Polymer Electrolytes for Li-O2 Batteries
Research Advisor: Dr. Yang Shao-Horn
Li-O2 batteries offer great potential in transportation applications due to their high theoretical specific energies, with a tenfold increase over the state-of-the-art Li-ion batteries. The commercialization of Li-O2 batteries is hindered by several challenges; many researchers recognize electrolyte instability as the most challenging impediment. Electrolytes commonly used in Li-ion batteries decompose rapidly in Li-O2 batteries, and the decomposition pathways are poorly understood. This project is computation-aided design of functionalized polymer electrolytes for Li-O2 batteries. We will first develop a comprehensive screening test employing density functional theory to compute four stability descriptors: bond dissociation energy, deprotonation free energy, nucleophilic reaction energies, and redox potentials. We will couple the screening with experimental stability tests to understand vulnerable chemical moieties at the molecular level, and utilize this knowledge to design stable polymers. The designed polymer(s) will be synthesized; their mechanical properties, bulk ionic conductivity and charge transfer kinetics will be examined. Strategies to improve ionic conductivity will be explored. Finally, we will assemble full Li-O2 cells using the designed polymer electrolyte; cell-level stability, round-trip efficiency, and cycleability will be assessed. This project will open an avenue to stable and ion-conductive polymer electrolytes for Li-O2 batteries that will power the next-generation electric vehicles.
Development of high performance and cost effective functional materials is a crucial research area for large-scale deployment of photovoltaics. Material platforms like CdTe, CuInxGa1-xSe2, Cu2ZnSnS4 and Organo-Lead halide perovskites have enabled remarkable progresses in pushing solar cell efficiency beyond 20% despite certain scalability challenges. This project aims to develop transition metal perovskite chalcogenides (TMPCs) as a new class of versatile semiconductor with earth-benign and abundant composition, broad tunability of physical properties, large density of states (DOS) and high carrier mobility for photovoltaics.
Representing an estimated 7% of world primary energy demand, approximately 2.7 billion people rely on solid biomass fuels for cooking. On a global scale, the combustion of wood, crop residues, and dung is responsible for 4.3 million premature deaths annually due to household air pollution. Impacts on the environment are also significant, as the harvesting and combustion of solid biomass contributes to deforestation, ecosystem degradation, and approximately 25% of global black carbon emissions. Improved cookstoves can dramatically reduce household air pollution, black carbon emissions, and fuelwood consumption by providing more efficient combustion or substituting fuel types, but it is often challenging to verify that improved cookstoves are being used appropriately and exclusively. With recent funding from the Department for International Development and as part of a National Institute of Health grant, our lab will explore how health impacts can be maximized through two distinct innovations: dynamic sensors that provide real-time feedback to end-users, and conditional cash transfers funded through health credits. As one of the first applications of dynamic, behavior-reinforcing sensors to promote and monitor appropriate cookstove use, this project will provide valuable insight into how end-user behavior can be influenced to improve household health and energy utilization.
If you would like to find out more about our Link Foundation Energy Fellows and projects that have been funded in the field of Energy by the Link Foundation, please visit the Link Energy Fellowship webpage at http://www.linkenergy.org/fellows/.