Leanne D. Chen

Graduate Student

Phone: 
650-926-2073

Fundamentals: In order to model reaction rates well, highly accurate barriers are required. However, because DFT calculations are done at constant charge, the work function and therefore potential may shift during a charge transfer process (in fact, the work function can be altered just by changing water orientations). One way to remove this artifact is to extrapolate to an infinitely large unit cell, which requires many calculations at increasingly large cells and is quite computationally expensive. To make the extrapolation more tractable, it is possible to extrapolate the charge in the double-layer using a capacitor model. DFT delocalization error currently prevents the successful implementation of this model and I am working with Dr. Karen Chan on solving this problem.

Applications: Metal-air batteries are desirable for vehicle propulsion due to their high theoretical specific energy which rivals that of fossil fuels, however they are plagued by a multitude of problems such as exceedingly large overpotentials (50 to 60% of the total theoretical potential) and corrosion of the metal anode (hydrogen production, capacity loss). Working with Professor Alan Luntz, my goal is to probe the fundamental productive and parasitic electrochemical processes in these batteries with ab initio simulations in order to find solutions to existing problems and to design improved systems.

My previous experiences with DFT include studies on Li ion migration in ceramic mixed conductors for Li-S batteries at Bosch (Germany) and elucidating the mechanism of photochromic transformations at Queen's University (Canada). More information about my research can be found on my Stanford Webpage.

Theory PIs: 

Publications

Al-Air Batteries: Fundamental Thermodynamic Limitations from First-Principles Theory. Leanne D. Chen, Jens K. Nørskov, Alan C. Luntz. Journal of Physical Chemistry Letters, 6, 175-179. 2015. Theoretical Limits to the Anode Potential in Aqueous Mg-Air Batteries. Leanne D. Chen, Jens K. Nørskov, Alan C. Luntz. Journal of Physical Chemistry C, 119, 19660-19667. 2015.